I've seen restaurants that required a QR code to get a menu. I simply walked out. Lots of other places to eat exist with more reasonable practices.

Forcing people to scan a QR code to see a price is a great way to use the data from their device to serve them a different price than the last person who scanned that code was asked to pay.

Anyone else who wants you to scan a QR code as part of a check in process can be told you don't have a phone or that it doesn't work. It's their job to figure that out.