Since 1982 they have been ignoring milk-production quotas imposed by Brussels and getting Rome to pick up the tab for fines they incur. But with monetary union just around the corner and Italy desperate to clean up its act so it can join the single currency on time, the tables have turned against them.
A few days ago the country's 105,000 farmers were told they would have to pay their own fines for 1996 - some 370bn lire (pounds 150m) - and would be expected to stick to European production limits. The result has been a revolt, with tractors out on the roads and farmers threatening a French- style blockade of Italy's main cities. In Milan, the tractors have cut off access to Linate airport, forcing passengers to drag their luggage several hundred metres on foot.
Much of the anger has focused on the same government that bailed the farmers out for years. Umberto Bossi's Northern League has muscled in on the act, portraying the stand-off as a conflict between honest farmers and heartless bureaucrats, as has the far-right opposition National Alliance.
The saga stretches back to 1982, when Rome first fell out with the European Commission on milk production. The Commission, seeking to curb over-production, set one quota and Rome, worried about its dwindling agricultural sector, unilaterally set another - thus sparking a "milk war" that lasted more than 10 years.
Periodically there were attempts to resolve the crisis, but the result was always an excess of Italian milk production and a flurry of fines that the government invariably chose to pay itself. It was an unrealistic situation, but one that the farmers became comfortable with.
As the commentator Giorgio Bocca wrote this week: "Farmers got the idea that the European Community was itself one enormous cow for the milking."
Since the protests began last week, the centre-left government led by Romano Prodi has been pulled in both directions at once.
It is desperate to clear one of the worst blots in its European copybook and relieve the public finances of a burden it can no longer afford. But the last thing it wants at a time of Maastricht-imposed austerity is a widespread outpouring of anti-European bile.
Its answer has thus been to plead in Brussels on the farmers' behalf. Yesterday the Agriculture Minister, Michele Pinto, asked his European partners for a more generous quota, pointing out that under the present regime Italy would have to import more than 40 per cent of its milk. Today Mr Prodi will meet the farmers to explain the sudden reverse in their fortunes. The farmers themselves, though, are in no mood to be fobbed off with lessons in the hard economic truth. Yesterday the tractors were still out at Linate and more protests have been threatened if they do not quickly get their way.