I still don't see why it has to be so black and white.
Why either "put your trolley away EVERY TIME or else you're a lazy feckless patronising twat who thinks people LIKE collecting trolleys!"
Or "NEVER put it away because the trolley man loves collecting trolleys and it's keeping him in work."
It's almost certainly somewhere in between and it is fair enough to put it away or not depending on your circumstances. If I've been shopping with a 6mo who's screaming for a feed and I have to rush back for the HV coming round, I've left the trolley (somewhere safe).
If I'm on my own, or with a sensible older child who can be left in the car for a minute, I'll return it.
If you've twisted your ankle or have angina and walking is difficult, leave the trolley. If you're haring around like a headless chicken trying to fit in shopping, work, caring for elderly parents, nursery-pick-up and cooking the tea, leave the trolley. It's fair enough for the supermarket to help you out.
If you're fit and well and have plenty of time, it's the responsible and helpful thing to do to return it.
I've sometimes left a pound-locking trolley with the pound in because I was short of time and couldn't leave small fighting DC in the car etc etc. I saw that as paying the supermarket a pound for the service.
And what's wrong with leaving it on the walkway? It's away from the cars and shoppers coming in can pick it up as they go by, that's what I always do.
And yes it does create work, of course it does. Tesco etc. take into account and budget for the fact that trolleys will need collecting. They need collecting from the trolley park anyway, which is there so you don't have to schlep right back to the shop isn't it? So Tesco do collect trolleys as part of the service.
And I know supermarkets where there is a dedicated trolley person, sometimes someone with learning difficulties who does not also have a job on the tills. I don't think that's patronising, it's giving that person a paid job, allowing them to be involved in society and do what they are able to do in exchange for a wage (like any of us, in fact). It's not patronising that I can have a job doing what I'm capable of, but wouldn't be allowed to be a police dog handler or helicopter pilot because I wouldn't be good at it. It's OK to give someone a job that reflects their skills and abilities. And PPs on this thread have said, some people do enjoy that job.