OR, people like the idea of a 'cute little kitten', but not so keen on the costs, insurance, neutering, yearly vaccinations, flea/worming treatments to name a few.
I knew a woman who would let her multiple cats breed, with each other, neighborhood toms etc. Never played with them/gave them stimulation.
She'd give the kits away, one woman who'd been given one of those kittens took it out in a fucking wicker shopping basket to show it off, when somebody enquired was that safe, her response was that one of her kids had sat on it and it had a sore leg, so it couldn't jump out the basket, because it was injured. Didn't take to the vet, kitten didn't live long. 
Eventually the woman who couldn't be arsed to get her 10-ish cats neutered decided she couldn't cope rang the RSPCA. Guess what? within 6 months she got another kitten, who had kittens when she was still a kit herself. Kept one, neutered neither, and the whole sorry story began again.
Sorry if this turned into a bit of a ramble, but the point I'm trying to make is that, yes, easy to find homes for 'cute kittens'. Who grow up into cats, which take time, care and money to be properly cared for.