Of course, as the CPRE well knows, there might be any number of reasons for its raffle's loss of popularity. The recession is not over yet, at least in the public perception, and people have been reluctant to give money in recent years.
But the National Council for Voluntary Organisations believes the National Lottery will prove better news for the Government than for charities. Research conducted into the effects of Ireland's national lottery showed a reduction of 4 per cent in charitable giving. Opinion polling in Britain suggested that the figure here could be as much as 7 per cent - a potential loss of pounds 190m to pounds 270m a year.
``We believe the lottery will make competition for funds much more intense,'' said Margaret Bolton, the NCVO's policy officer. ``Small organisations will have more difficulty in raising money - the big charities can always find the resources to pull money back in.''
Charities could not expect that people would still be happy just to give money away, she said. ``Charities in Ireland said that fund raising had to re-orientate itself to give people something for their money. The same thing has happened in New Zealand. There is a growing culture of people expecting a return when they give.''
The lottery could also lead to a change in the public perception of what constitutes ``a good cause''. ``The lottery could encourage people to see sports and heritage projects as good causes,'' added Ms Bolton. The result could be a diversion of donations away from social projects.
It will be a long while before it is clear whether the lottery produces new money for charities, or whether it reduces it. The Institute of Charity Fundraising Managers has already expressed its concern at the way the lottery is being promoted, by lodging a complaint with the Advertising Standards Authority against Camelot, the organisation operating the lottery.
``In our view the advertisement placed by Camelot could lead the public to believe that the lottery provides an efficient and effective mechanism of supporting charities and voluntary organisations,'' said Stephen Lee, director of ICFM. ``This is not in fact the case.''
However, charities are not unanimous in the view that they will lose out.
Both the Salvation Army and Mind, for example, believe that their supporters are religious and will not gamble, and that income will hold steady. Mind, indeed, is one of the charities that hopes to gain from the lottery when the income is distributed.
Many charity workers, though, are worried the public will be unaware that just 5.6 per cent of the lottery's proceeds will go to charities - another 5.6 per cent goes to each of the Arts Council, the Sports Council, the Millennium Commission and the National Heritage Memorial Fund, with 12 per cent going to the Government as tax, 5 per cent to the retailer, 5 per cent to Camelot and 50 per cent into prize money.
This has led several charities to change their promotional strategies. On Saturday the CPRE is launching a new payroll giving scheme, emphasising that this enables the charity to be directly helped by donations.
The Cancer Research Campaign believes new opportunities are created. ``It could increase the income from other lotteries such as raffles,'' suggested Louise Pollen, national events and sports manager at the charity. ``It may encourage people to gamble more than in the past.''
Promotion of the CRC's own raffle is to be boosted, and it is seeking a long-term agreement with a car manufacturer to supply prizes, allied to a more comprehensive raffle ticket distribution arrangement, including through car showrooms.
The long-term effects will depend substantially, according to Ms Pollen, on how the lottery is promoted. She is relieved that initial advertising appeals more to self-interest than to altruism.
That view is not universal in the charity world, as Michael Taylor, director of Christian Aid, explained. ``We positively hate the ads.'' He has other concerns as well. ``We are supposed to be working for the poorest people, who have already lost in one lottery - I don't want them to lose in another.''
More optimistically, Mr Taylor added: ``I know our supporters well enough to think they will not be seduced.''
Many large charities are similarly confident that regular, committed supporters will not reduce their gifts. ``It is the scratch card promotions, street tins, buying a raffle ticket in the pub that will be affected,'' said Clive Caseley, appeals and marketing director at Mind.
But the other question mark hangs over future responses to emergency appeals, which need casual donations. Oxfam, which raised pounds pounds 6m from the public for the Rwanda crisis, is worried whether its capacity for similar campaigns in the future will be reduced.
The Salvation Army, though, is supremely unworried by the lottery.
A spokeswoman commented: ``People who subscribe to the National Lottery want to get rich quick. They are not the people who want to subscribe to charities.''