Yes you're a bit mad. Holidays is holidays. A dirty car proves you've had a good time.
We don't mind dirty car pics in lovely places. Enjoy your holiday.
I've never carried any cleaning in the stuff when I've been away - it's never actually crossed my mind to do so either........that said after long pan European trips when I've got home I have got the pressure washer out quickly to get the worst of the 150mph+ bugs off the front