For a community long accustomed to unusual restrictions on the sale and consumption of alcohol, it’s been a remarkable change of pace for Gainesville to amend its ordinances over the last year or so to accommodate businesses serving up beer, liquor and wine. But the thirst of some to scrap or modify one of the city’s most contentious regulations on alcohol has not yet been quenched. The city requires that restaurants selling alcohol make half their revenue from food sales.