Watching the Drug dealers
If we make that harder, the police will not be able to selectively enforce drug laws against the competitors to their favorite dealers, who are obviously upright citizens, what with the frequent contributions to the widows and Orphans fund.
That could lead to a rapid growth in the "suggested donations" from pretty much all small businesses. When the pub starts passing that tax on to their customers, there may be some resistance from the electorate.
(Above is based on happenings in the U.S. YMMV in the U.K.)