Three people doesn't have to mean three entrees and three drinks. We almost always drink tap water and can usually share an entree.
EDIT: And I'm a fat guy FWIW.
My husband would think I was nuts if I suggested sharing an entree. And he's not fat.
Sometimes my daughter and I share, but I get tired of always having to negotiate what we're going to get. It's not crazy to want to make a selection of my own.