Tough (incorrect?) fold at Trop
 

Was playing at a loose passive 1-2NL table at Trop, with people limping with all sorts of crap (A6 offsuit, any suited, etc.). 6 people limped to the flop. I had T8-spades and was 1 off the button, so I limped. Flop came:

A 7 3, all spades

SB bets $10, gets 3 callers. I probably should have raised but just called. The button raises to $25, 3 folds. I re-raised to $75. He puts me all-in for my remaining $125.

After a long thought, I folded. I've been thinking about this decision for a while and am still unsure whether it was a wise fold. Would appreciate any expert thoughts.