Families really mess some people up with their made up rules. Meet a girl that was raised that you can't talk at the dinner table. She thought it was normal to sit down, eat an entire meal, and then get up in dead silence.

I remember meeting someone in high school that was confused that everyone was eating and drinking in the same meal. Because in their house and extremely limited world view, you EAT. Then you leave the table and go DRINK.

I think you're right. I guess they had parents who were big on setting rules, but not on justifying them.

I'm pretty sure my parents throttled my bread intake at restaurants when I was very young for the reason you state, but they accompanied their directive with a "don't fill up before you get your main course" justification. So I didn't assimilate it as a rule of etiquette, and instead understood the underlying logic.

Ehh ... It's more likely etiquette to not descend on the rolls like a starving Labrador retriever. Much of manners is about self restraint and making oneself 'small'. The idea is that you wait a minute or two, so it's not like being at the Chinese food buffet when a fresh load of sweet and sour pork comes out. Everyone piling in for the rolls is undignified. It's related to the idea that even if you really want that last roll, you ask if anyone else would like it before snatching it for yourself.

... but judging someone for grabbing one when they come out? Pretty prissy.