JMHO- I get tired of smelling cat pi$$ and stepping
in turds all over the yard.
The " cat lady " doesn't own any, but keeps food
out 24/7 . That same food attracts possums and
skunks. During the warmer months, you can't step
out on the porch to check the mailbox without
getting a few fleas on your legs.
Yeah, feral cats are pests

I'm told that a 220 BG works really well with a little
dry cat food in a bucket set, or some of the cheapest
canned fish, mackerel etc.
A 160 BG is a bit better for the average sized feral feline

Or so they tell me. . . . .