I'm quite familiar with the way it works in the US. If it's a birthday dinner or your circle of friends then yes people will likely split it evenly, but if you are a mixed group of people then people will generally pay for what they had. But regardless if its just "60 bucks a head" everyone at the table needs to settle up, and everyone throws in cash in a pile and takes their change out of the pile and then the pile needs to be sorted and counted and sometimes its short etc.

Only assholes ask for this. It's definitely not the norm. This is the fastest way to encorage me never to eat with you.