Lunch and fuel stop somewhere in Southern France?

I would say yes you do. Don’t overlook police/customs stuff.
Of all the ones I referred to, only Lyon and Saint Etienne have customs with PPR 24hrs. Grenoble LFLS usually have onsite customs but its PPR now with covid. Colin’s suggestion look great too.

Thanks both Juju and Colin. I didn’t consider the immigration angle (coming from Uk) because I considered that if I just refuel do I really need Schengen check?

You could try LFGJ Dole Tavaux. It has various instrument approaches as well.

I have stopped there several times when going south from the UK as they have Immigration as well. There is a restaurant but I have not eaten there. Fuel is available at a good price usually and can be paid by Credit Card or AirBP Card. When using a Credit Card the Pompier has to come out and turn the pump on.

The staff are always friendly and helpful.

VAC and SD reports agree that avgas is sold from a self serve pump taking visa cards. You can phone one of the local clubs to make sure it works.

If you need to divert, I would say Bron LFLY is a good choice (well equipped, GAT and long opening hours, with hotels and restaurants nearby). They would take any credit card too. Also it is in the Rhone valley so better radar coverage and easier terrain.
Cheapest would be Saint Etienne LFMH (notam says they take credit cards during fueling hours), Roanne LFLO (un controlled, certainly the cheapest) or Saint Yan LFLN (mostly flight training activity).

Merci Juju. Should I phone somebody at Villefranche beforehand to make sure avgas is available and that visa (non-total) card is accepted (I read an old comment on you-fly about this recommendation for LFHV)?
Also, can you please suggest the cheapest ifr avgas-stop alternate nearby, in case of bad weather?

Villefranche LFHV fits the bill.

Sorry for restarting an old thread: can somebody recommend an avgas stop near Lyon (max 50nm away) for my rv7a? Should be cheap (both avgas and landing), accept visa/mastercard (or cash), and with tarmac runway (no grass). And not an altiport. Thanks

Should " Mama Mia " be closed there is another restaurant at the airport just 150m walking distance towards the first roundabout, called " Grill Courtepaille ".
Open from 1100 to 2300h. Not bad – I was there for lunch last August waiting for friends arriving delayed. And that was around 1500 local …

Good! Added to the mental list!

Avignon is a great destination anyway, especially during the incredible annual theatre festival in July.