I see nothing wrong with that what-so-ever. We have to make up for the idiots in the world! When we're trapping at the park whatever cat is in the trap without an ear-tip gets fixed. If it's a neighborhood cat that happened to wander over that day, well they just got a free neuter/spay job is how I look at it. I must confess we also trap in our yard. If they're not fixed, they will be!