There are stray cats in my building and my cousin bought them food, however I am not going to give it to them.
What is your reasoning for not feeding the cats?
I do not feel comfortable with feeding the stray cats especially when they already have enough food to survive on.
It was nice of your cousin to think about the cats' wellbeing, but you're right on this. The cats have enough food to survive on and they're strays, so you aren't expected to feed them in the first place. Doing so will likely make them reliant on you and they'll keep coming back for more.
I do get why my cousin bought the food though, it was to help them.
Your cousin definitely had good intentions, but feeding stray and feral cats isn't necessarily a good thing and it's definitely not something you have to do. Perhaps you can ask around and see if someone wants a cat and they would be interested in taking one in their home permanently.