The French police are not averse to a bit of cash fund-raising. Living here i do hear the stories.
Also i was once stopped in a ski town, for apparently not stopping at a Stop sign.
I said 'What Stop sign?'
They showed me. The sign was covered by a tree branch laden with snow, and the white line on the road was covered in snow. 90 Eur cash fine. But i did and always do make sure i get an official ticket.
Nobody carries the breath testers, but you do still see them occasionally on motorway service station counter with signs in English saying 'compulsory'. Another scam.
Incidentally they are totally useless. I had a accident a few years back where someone drove into me and the drove off. Not my fault, but i had drunk a beer and a half (under limit). However I thought it wise to use my tester before calling the cops out. Mine indicated nothing, theirs indicated me at about 75% of the limit.