They do. The alcohol dealers can only sell via licensed dealers and are punished for selling irresponsible products and to people irresponsibly. To drunk and you sell them more, you can get your licensed revoked, fined and possibly further penalties depending on where you are. If a you sell to a customer and they get drunk you are legally required to provide them with a safe means to get home most places. Whether that be providing a cab if necessary. Usually they will just call it for you, but often times that is them just dodging paying for it as they could be held liable for it. If a drunk driver leaves your establishment and kills someone, the establishment is also held at fault.

The people are told to drink responsibly.

(Not saying alcohol laws are perfect, but yes, they restrict irresponsible sales as they should restrict misinformation, and the company selling it is the one responsible)