We almost got scammed like that once many years ago.
We were in an airport and these guys were at a table promoting frequent flyer miles. Sounded real good but it turned out to be that you signed up for a credit card, but they weren’t telling you that part.
We were PISSED when we found out. Read the company the riot act about fraudulently representing the card, and got out of it, and NEVER fell for anything like that again.
Airline miles and other “perks” enjoyed by those comfortable enough to rack them up are fully funded through higher interest and late fees coughed up by those who aren’t.
Cabela’s tried that in Boomtown. Same technique. I locked up when they asked for my SS#.
Paid cash.