Do they make you order food with every round of drinks? I remember hearing about places like that from my dad, and it seems it would have worked better in the era of cheap drinks/low built-in alcohol taxes.

I went to college in a county that only allowed alcohol sales with food for clubs (think: country clubs). So, of course, the restaurant that I worked for created its own club. You simply filled out your name (and maybe phone number, I don't remember) on a piece of paper when you ordered your drink.

They easy way would be to do like in some parts of Spain, for every drink you receive a tapa.

That way it can be considered that the food is part of the price of the drink.