When you have too many males in one bin they will fight each other to be able to breed with the females. The ones that have their wings bitten off are the weaker ones. You should slim down the number of males in your bin and that will help with your problem.
I am not sure then maybe if you replace your males with new males every so often. Or see if you can throw in some different types of food. The females could be doing the damage also if the male tries to breed with a already pregnant female.
I buy the roach food that the roach guy sells on his website. I think it is cheaper then buying everything and taking the time to grind it all up. I do ocasionally have problems like this but it is because I have to many males in one cage and I just feed the beat up ones off.