Thayer isn't a kid he's got to be like 40

If you recognize them but they don't recognize you, then it's a no brainer fold. if you guys do know each other...then it's hard to say.

I generally wouldn't try to hero here...it's a live mtt after all and ppl just don't go out of line as much as they do online.

doubt this is true in the 1500 wsop 6max. i think i fold river though.

No.

Don't fall victim to FCS--fancy call syndrome. Find a better spot.

Your opponent has some random straight draw that mighta turned into spades or just made a straight and he decided to go for max value because he thought you weren't folding on the river and he sucked out and didn't take the time to think about how much to bet.

Surely folding, it's interesting and not simple, but with basic analysis, seems like a simple fold. If he's doing this he'll try it again and you can adjust your calling range at that point. With no information, you should probably be the aggressor vs better players just because it's much harder for them to stand up to or manipulate than you being passive.

Fold and change your strategy to something more conducive for your skill vs the table's skill.

if you check the turn back it seems unlikely he can bluff you on the river. not sure how much you can rep with a turn bet anyways.