Honestly, that reaction was kinda retarded on Hammer's part. It's like when you say something to someone using a word they don't understand, and instead of trying to figure out what the word means, they instantly get mad and want to fight.
You got to be careful when insulting any dude's mom because you don't know how to react. But I don't know how anyone with a brain couldn't have seen that that line wasn't a literal diss to Hammer's mom, but a play on the words from Hammer's song. On top of that, Hammer always rolled deep, he could have just seen them dudes and whooped their ass if he was offended. Calling a hit was way over the top.