Could also be due to glass repair companies taking the piss and wanting to replace whole windscreens every time someone has a small chip. I had them take a look at a chip which had been repaired by a previous owner, and they were very keen to replace the whole screen for free - but I chose not to as it was well below my eye-line, and I figured I'd increase the risk of just creating leaks or not getting a exact like-for-like replacement.
6 years later and I still have the repaired chip... Has been months since I even last thought about it.
Totally agree with an earlier post which spoke to only targeting those with particular cars. Both my cars have rain sensors and it's not exactly like the cost to repair my screen is going up to the point I should have to pay more for the same or less cover.