Hm... Maybe infected bounty rewards are something like quality item chance which drops down when you find a quality item for a period of time. I think everyone noticed, even DMU players that after some really intense scavenging you get only black/grey/green or blue items at best.
Allow me to describe my personal experience and a situation I had. Some time ago, discouraged by tragic bounty rewards (green kits and smoke grenades) I began to ignore infected bounties. I let about 5 of them to expire, then, tired of fruitless looting I took 2 week break from the game. When I returned to play, I've found 3 uniques and 2 rares in one day (no DMU just UCS-50% and 4% shiny) and when I finished the infected bounty, the reward was surprisingly nice (at least for me). I cannot provide a screencap because I don't screencap such things but it was something like 180 fuel (1 slot was 100, another one was 80), LVL3 HERC card and 3 rare swifthand kits which I gladly used to craft ammo mods. Maybe it's just my isolated case or maybe someone had a similiar situation (Anyone, hmm?). I don't know people... It's just random numbers generator and dice rolls, just keep trying. Or test my method of letting few infected bounties to expire.
As for the "GREAT!" button itself, well, I don't care much about it but I'll suggest nonetheless that it could be changed to simple "Ok", because "Ok" can express all 3 types of feelings towards infected bounty reward, positive, neutral and negative, where "GREAT!" is positive only.