You have a lot to learn young Adam, women are mad creatures, but as stated above if it was a cheated wife that did it I'd suggest she'd have scrawled something more along the lines of "cheating *******"
"Rich c*nt" would suggest it was more like a random attack or perhaps someone that had lived in a rough area for a while that had just started to make something of themselves by legitimate means and the scum neighbours didn't like it.
I grew up on a council estate and when I was about 12 my Dad started his business, it grew rapidly but it was kept very low key in the eyes of our neighbours. When I was 13 me and my Mum had a head on collision in an A reg Sierra, a 6 year old car at the time. It was written off and my Dad replaced it with a 2 year old Volvo 740GLE, which at the time was a very desirable car and the choice of the middle classes. We had it a week and it was keyed bumper to bumper, bonnet and boot. We moved very shortly afterwards.
There's plenty of scum in the world (including the mother pushing a buggy that spat at me in my Aston Volante at traffic lights in Southampton a few years ago) that would think they were some how justified to do this kind of thing because someone is "rich". So yes, they should be hung drawn and quartered as reasoning with them that someone had WORKED hard to get whatever they have and therefore deserve it simply wouldn't work.
/and off the soap box.