I used that analogy because it’s painfully clear how it can go off the rails. The common thread is that legality isn’t simply waived in all cases. Legality is determined by reasonableness and, in some cases, by an expectation of duty. I don’t believe the Chevy example constitutes a contract but not for the reasons you’ve presented. Thinking you can just say “lol nothing here is binding but thanks for the money!” without understanding broader context is indicative of a cavalier attitude and superficial understanding.