- Would the following annoy you if you were in my shoes?
- Would you bother to complain?
No
No
Being a 1K and regardless of passport origin, does not exempt anyone on any airline from being randomly checked at the gate. With the state of world affairs I welcome the checks as a last ditch effort that no one sneaks on the plane, and also I am sure the GA just wanted to double check that all was ok with your passport. GA's do not memorize which country allows free entires for other passports. Even with the bp check stamp, random checks can occur.
I am suprised that UA gave you 5000 miles compensation for a GA doing their job but consider yourself lucky.