Finder denying rescue efforts

I just want to vent. While looking for my lost cat this morning, I started chatting with a couple in my neigborhood on a walk. They mentioned they have a momma cat and her 6 week old babies in her backyard that they’ve been feeding. I asked if I could trap them, to spay/neuter and find homes. I could even do this outside their back gate (townhouse community). They aggressively denied. I continued to express the issues with not fixing cats and pointed out our already overpopulated feral community. These are babies that can be in a safe warm home with their mama, and she is denying them that. They were extremely rude, and selfish. I’m new to the TNR community, I have rescued and fostered. Came across some frustrating situations but this is just so infuriating to me. I simply dont understand.

Why be a problem when you can be a part of the solution?