Yes I agree, though my thing for the owners would be to neuter them as well, before doing the drop off in a strange place to fend for themselves. My place to drop off would be a nice clearing in the Taiga, middle of summer, where you can travel by plane for 3 hours in any direction before you find anything approaching a hut. Would not be totally heartless, I would allow them the luxury of having a t shirt and pants on, plus a pair of flip flops, and a blunt kitchen knife.
But then my cat likes going outside at times, though he is an indoor cat, and has a great aversion to people, seeing as I got him as a doorstop stray.