Perhaps. The main difference, however, is that fiat stamping would be much more difficult to enforce considering there isn't a public ledger to verify your compliance. Also, the existence of larger merchants with publicly known addresses would greatly reduce the foul play you described. These merchants would be the first to comply, with the smaller "honest" merchants eventually falling in line. A slippery slope for sure, but definitely a point of weakness in the decentralized nature of the network.
While not all do, I would anticipate most major merchants, if not all, implementing hourly/daily address changes, there is 0 benefit (aside from tx fees, much smaller the CCs) to having 1 big fat address vs. many smaller ones...