Our local tip is so heavy on their rules, which they enforce unwaveringly without applying even a modicum of discretion that it is infuriating, so while I would never condone fly-tipping, I can see why it happens.
A couple of years ago I took down an old shed and put some of it in my FIL Escort type van (he’s retired but still has a van) and the rest in the back of an estate I had at the time. We went to the dump, started unloading, and a drunk with power employee told us we weren’t allowed the van. So we unloaded the car, and then had to exit the dump, just outside the dump decant the van into the car, and return. It was laughable.
I tried to make the point that it was domestic waste, and we’d by 5 minutes, but they just weren’t prepared to listen.