Why does everyone always assume that if minimum wage went up or if tipping went away that the customer would absorb the cost?

There’s no technical reason for why, just based on current evidence where 100% of the time producers shove any increase in cost to consumers.

You’re correct that there’s nothing technically preventing producers from eating the increase, it’s just that they’ve never done so, at least in the US.

Only real example where that has happen was with Nintendo and the WiiU. I’m sure there’s more but the fact I’m drawing blank past that but could name you over a thousand times when the cost was shoved off to consumers kind of is my point in a nutshell.

So that said, that’s why a lot of people just assume increase in cost of production equals increase in cost to consumers.