Joining into the thread a bit late here, but whatever.
I honestly have to agree with Mouse with this one, although the FNaF and MLP fandoms cut it pretty close.
Why? Let me explain.
Despicable me 1 main focus was this scientist named Gru, who was up to his usual scheme's, with the help of his minions and his assistant, to try and capture the moon with 3 girls tagged along.
Now when I saw the fandom, it was just minions. No Gru, no girls, not even forgetin Fred McDade. Just...
MINIONs
And it's why I hate the fandom as a whole, because of those loving minions. Why did THEY have to be created? They could have made a whole new worker, and I would have been fine with that. but no.
The fandom also went over the loving ROOF. so now we have a movie ONLY based on the Minions simply titled, MINIONs.
The fandom just won't stop talking about it, and it's pushing me up a loving wall here.
As for the others, they have their up's and downs, but Despicable me takes the cake, simply because of minion spam.