If I walk into a bar and order a drink I expect them to ask for ID to prove my age. If I walk into a McDonalds and buy a Big Mac I would not expect them to ask for ID to check my age and if they did I would not expect them to photocopy it and give it to Fred to keep in his poorly locked file cabinet.
@grumpygamer
Instead of copying your ID, can't Fred, knowing you are you, and old enough to buy and consume that Big Mac, issue you with a unique, but otherwise random code, not linked to you, but verified in person, which you could also use in Wendy's or Taco Bell? They will know you are a suitable patron, so you can have BBQ Bacon Melt, Big Mac or Volcano Burrito as you prefer, and no-one needs to compromise your Id. (I know some people can"t get to a restaurant but the principle stands)

@SometimesLovely @grumpygamer
Or, which is a lot cheaper and has fewer moving parts and places where something could go wrong, they could just mind their own fucking business.

If you want to somehow go and do unspecified crimes with the burger, that's a separate problem that has not been quantified or even proven to exist, so does not require policy to be imposed.