Villain is completely unknown, so he's not a reg.

This is like third or fourth hand vs him and he has been folding so far. His bounty is $1.70 (so I'd be getting $0.85).

PokerStars, $6.82 + $0.68 - Single Draw 2-7 No Limit - 25/50 (12 ante) - 6 players
Replay this hand on Upswing Poker

UTG (Hero): 2,593 (52 bb)
MP: 1,827 (37 bb)
CO: 4,892 (98 bb)
BU: 2,913 (58 bb)
SB: 2,922 (58 bb)
BB: 2,698 (54 bb)

Deal: (147) Hero is UTG with 8♣ 4♦ 5♥ 9♥ T♠
Hero raises to 150, MP 3-bets to 1,815 (all-in), 4 players fold, Hero? (1,665 to call)

I'm pretty sure you are calculating the bounties incorrectly. Relatively recently, Pokerstars changed how they show bounties in progressive knockout tournaments. It used to be that half of the shown bounty goes into your account and half onto your bounty. Currently, the full amount shown goes into your account and the same amount goes onto your bounty. The amount currently shown is half the amount that used to be shown. Assuming your $6.82+$0.68 tournament is a 50% bounty as most of these are, the starting bounty is $3.41, so the number shown under the current system starts at $1.70. You would get that full amount. It's very important you understand this or else your decisions will be misguided.

As for this hand, seems like a very standard call and pat, even without the bounty. The bounty just sweetens the deal.