Merc drivers are fine.
BMW drivers had a reputation for being appallingly aggressive drivers, but that mantle seems to have been taken by Audi drivers in the past few years.
Nine times out of ten, if you’ve got a car right up your backside, it’ll be an Audi.
I think it goes in phases. Audi’s (especially the A3 & A4) seem to be the estate agent’s favourite at the moment, which might explain it.