That is a lovely post, in so many ways, WomanActually.
Our nearest cinema won't let you book the disabled seats (which are actually just a space with 2 seats removed - no cupholders or anything) - in their online system. You can book all the other seats online. To book a disabled "seat" - ie wheelchair space - you cannot use an automated system but have to call their management office 9-5, Mon-Fri only. So no booking the cinema over the weekend for Sunday morning.
They explained this is because people who do not have anyone disabled in their party book the wheelchair spaces online when they make them available for booking. The spaces are in the front row and between two standard seats so I suppose they look attractive to some people who would like to let their toddlers sit in their buggies in a wheelchair space in the cinema.
Obviously we can't go in if those spaces are booked - fire safety restrictions. So we can't really take a chance and just show up. So it's actually better if they make those spaces harder to book. But having to jump through those hoops adds another layer of difficulty and planning where it would be nice to just go the cinema.
I hope threads like these go some way to convincing people that (mis)using facilities which are designed to give people with disabilities a bit of access has knock-on effects, even when they've been thinking it "does no harm/it's not being used anyway/ I'd move if someone "disabled" came along"