But TBH as I've nothing to hide, it doesn't really bother me whether they ask me now or at check in and neither should it anyone else who is genuinely authorised to use the code.

The thing that would bother me is if they have to double check with my kind friend every time I book something .. I would feel like I was being a nuisance then.

But why would I want to be confrontational with someone who is granting me a benefit I value ...