If I see someone parked over the lines I will always cram myself into the space left. I drive a tiny Combo van so that’ll fit in most places.

I have asked someone (in an Audi, funnily enough) to repark their car at Ladybower when I was visiting from Scotland once. There were no spaces left and he’d parked with loads of room on both side, reducing the gap so it was just small enough to not fit a Honda Civic into. He was fine about it, he didn’t even realise.