I don’t understand. No law prevents anyone from doing what’s forbidden. Are you saying all laws are futile? Otherwise what is different with this law that makes it futile?
Also, we usually can do many things at once or in succession. We can raise prices on sugary food, start programs to inform the public about the impact sugar has on health, make school lunches more healthy etc. Would you complain that it is futile raising prices if it was the first thing proposed or would you say “Good, let’s do this and also the other things.”?