I totally get that it seems unfair, but to be totally honest it’s mostly unfair to the cats to be in a situation where they’re living on the street. It’s amazing that some of your neighbors was helping these feral cats but cat colonies like this is really not a great thing for the environment. Cats have extinct many different species. That’s a serious issue for the environment.
My cat Raymond by the way is from one of the many colonies in my country and trust me, I would rather have them taken to a shelter where they are hopefully adopted, than let them stay in such a colony.
These are not adoptable cats, else they’d all have been homed already.
I’m not an vet, but most of the cats should be able to be adopted. These are so called “scared cats” and my cat Raymond was on the street for at least 1,5 - 2 years before I got him. He was taken directly from the street.
Funny thing, I contacted the local animal shelter and asked if I could be a foster home for a cat, and it took them just over the weekend for them to contact me and tell me they had one for me. This was the summer of 2020. This time of the year is high season for dumping of cats on the streets… And well you see the results in this case.