I completely understand not being able to take them to the vet!
No flames from me at all.
But I wanted to tell you that in our area if you take them home and start feeding they are considered legally yours. And if you don't seek vet treatment for them you can be charged with neglect, animal cruelty and a host of other things. This may not be the case where you are. So feel free to ignore me.
But I know this first hand - having watched a sweet old lady trying to take care of stray cats. The charges were dropped but only after a trial and a huge mess. She was charged with neglecting to seek vet treatment, animal cruelty, and honestly I can't remember what else. Some of these charges carry jail time. The charges were dismissed in court and the cats were picked up by animal control.
Once you start caring for them they might be considered yours.
It stinks that you can't turn them in either.
I have no idea what the solution is. Dh and I have taken in more strays than we can count. Some we have kept and some we haven't. But after going through this court ordeal and watching this 80 year old well meaning lady face this, I will not bring home another stray that we don't intend to keep. We can't afford to treat every stray we find either.
It's great that you are taking care of them though - poor kitties!