We are booked into a premiere classe hotel enroute this year, they were offering family rooms (dbl & 2 singles) try their website, one on your journey may have a similar set up. It's worth checking.
Don't forget to leave a review of the French and other European campsites you have visited!
I dare say that you can get 'robbed' anywhere ... but, have to say that we've never had a problem, including at any F1, and we've used plenty over the years, including ones near Calais! And leaving full rig of loaded car, roof box, trailer, bikes on carriers etc.
Just leave everything locked up ... car alarm on ... don't leave any obvious valuables in full view ... we always cover with blanket or some such.
Take you bag of very valuables (passport, wallets, cash, laptop, mobile etc) into the hotel with you.
A day of all things motorhome and campervan. The show is held both in the main indoor arena and across the grounds. Catering, hot drinks and food options are available. Easy access to the site and free parking included. Win one of five pairs of day tickets