What? Speak up! I can't hear you!
It actually takes a law to make them comply with a common sense measure? Not really... there's a number to call if they don't comply. That's so the government can levy a fine on them. Then they'll raise the price on the advertised product so that the consumer covers the cost of the fine plus a bit more, since they'll never drop the price back again.
Cool game. Can anyone play?
edit:
The public is screwed, no matter how you look at it:
1. Companies comply with regulation: Prices go up because "that costs money".
2. Companies don't comply: Prices go up to cover fines.