Every day, I'm asked to support a charitable cause – to do a funny drawing, send a signed book, go on a group walk, donate a pair of specs or a frock. Sadly, it rarely involves just sticking my hand in my pocket, handing over cash or writing a cheque. It's as if charities think they need to sugar the pill of donation by coating it with a "fun" activity – so donors get something in return for their generosity: an object bought at auction, the completion of a physical feat, like today's marathon. Once people ran long distances, walked across countries and climbed high mountains for the pure challenge and the sense of accomplishment; now, 99 per cent of the time, these activities have to be carried out for a good cause.

What a shame the simple act of giving has been turned into a sport, an entertainment, a telly programme and a midnight mass spectacle. These days, charity has to give us something back in return for our bucks. Successive governments went along with this notion, giving tax relief on charitable donations, and as Britain ran out of cash, they increasingly relied on funding a huge part of our education and cultural offerings by making charity hot and sexy. I disagree. Why should the mega-rich – who can afford skilled financial advisers to ensure they only ever pay the bloody minimum they can legally get away with, anyway – get handed a load of tax relief simply because they've handed over some of their excess wealth to the less fortunate? As far as I'm aware, Jesus didn't specify that by helping others you got a bit closer to heaven with a generous tax break thrown in, as well as your name immortalised on a plaque. Helping others should be a selfless act, untainted by tax considerations. Even worse, these days wealthy donors get another accolade which really gets my goat: they are routinely awarded gongs- for their "charitable works". In any religion, doing good for others is a moral imperative, not a foot on the ladder to a knighthood.

The super-rich not only legally minimise their tax, they launder their image by using charitable donations to promote their businesses in the media (ie, via the BBC telethons) and get to meet and mingle with the people who run our country. Most ordinary people donate a higher proportion of their disposable income each week to charity, via the Lottery and telethons, than any millionaire who gets their name on a building or a university college. Ordinary people don't have the option of tax avoidance or "wealth management"; they are on PAYE, taxed at source, unable to meet the PM. Most big charitable donors are so wealthy they are earning money from money via investment and trusts. Ordinary taxpayers fund the NHS, the police force, the prison service and our care system out of the hours they put in at work every week, not via their investments. Why should public schools – where these rich donors send their kids – have charitable status?

As for George Osborne's new proposal to cap the amount that the wealthy can give to charity and set against tax at £50,000, or 25 per cent of the donor's income – what's the problem? Our whole relationship with charity is already too skewed in favour of the rich. Personally, I'd impose a blanket charity tax of 10 per cent on anyone earning over £150,000. We are told that the building of hospitals, universities and museum extensions will suddenly stop if Mr Osborne has his way. I hope he calls their bluff – rich people always whinge (it's their default reaction, usually issued by their expensive PR agencies) whenever anyone implies that perhaps they could pay a tiny bit more towards the running of Britain plc. Lower down the income scale, middle-class families have seen a far greater fall in their disposable income. Food prices have risen, the number of women and young people out of work is at an all-time high, and we're asked to feel sorry for millionaires? Such tosh is written about the British "culture of giving". The truth is, those who can afford the least already give the most.

Let's look at the income of MPs' wealthy spouses, too

Politicians have a new buzz word: transparency. Since George Osborne's bonkers decision to reduce the top rate of income tax from 50p to 45p in the pound for those earning over £150,000, there are calls for him (and his fellow Tory toffs) to 'fess up and show how much they hand over to HMRC. Dave says he doesn't have a problem, but Nick Clegg has gone even further.

Mindful of a poll showing the public's faith in politicians at an all-time low, he wants all politicians to publish their tax returns. Tax experts say this tactic would reveal very little, as many MPs offset their rental income against mortgages, making it hard to work out exactly what they do earn, and how much their property and assets are worth.

Mr Clegg says he doesn't think spouses should be included. Miriam, a high-earning lawyer and director of a Spanish building firm, probably brings in more than he does. Sam Cam comes from a wealthy family and has shares and a high-powered job at Smythson. Ed Miliband's wife is a successful lawyer. In my book, transparency should apply to the whole household. Politicians flaunt their wives at every occasion when they need a few votes, so why shouldn't we know the exact nature of their financial partnership?

Women can do better than this

Telly 'tecs Scott and Bailey have received a big thumbs-up from the sisterhood, possibly because most police series are so macho. Every Monday, seven million ITV viewers have been following Janet Scott and Rachel Bailey, played by Lesley Sharp and Suranne Jones.

Sadly, the show leaves me cold. One critic raved it was supportive, without bitchiness, but the result is dreary beyond belief. I don't need telly to transmit propaganda about feminism in the guise of a cop show, thanks.

For top entertainment, see Headhunters, the film of Jo Nesbo's brilliant thriller. It's audacious, violent, and very funny. The leading man is a psychopath, who meets his ultimate challenge – someone who is even more unpleasant and cunning than he is.

Heaven is a seven-stile walk

As a passionate walker, I want our beautiful countryside to be enjoyed by as many people as possible, but the news that the Dartmoor National Park Authority plans gradually to replace stiles with "gaps" and gates seems a touch heavy-handed.

Stiles are a traditional part of the landscape, like dry stone walls and kissing gates. Why should every trail in the wild areas of Britain be accessible to all?

Of course, there must be plenty of paths in our National Parks and Areas of Outstanding Natural Beauty that are suitable for the elderly and for wheelchair users. But as for the obese, I would have thought that navigating a stile was valuable exercise that can help shift unwanted pounds.

Let's not take the challenge out of rugged walking by turning it into an anodyne toddle.