You're funny.
When I went to France in 1992, they had nothing american at all. I was there for a year, pining for ridiculous things like Doritos and Oreos (and peanut butter). However, when I returned for a visit in 2003, it was a different place. The american cookies and cereals and junk was all there. I don't know if that's necessarily a good thing.
One of the things I've always admired about the french, is their inclination to eschew anything too "american" (except our Levis of course). They seem to have a better handle on the concept of moderation, when it comes to their food and eating habits.

For what I would miss NOW in terms of american food....nothing. Wait, I lied...candy with peanuts..the french love to use their precious noisettes in everything (goo).

What I miss from France....the cheese. Now, you know you LOVE cheese, when even your french friends call you "cheese monster". In american grocery stores we have one little section of imported soft cheeses along with our nasty, american processed junk. In France, there is a whole aisle, if not two, devoted only to cheese.

Oh yes, and Tahiti body soap.

Good luck with your move Asterix. Please, tell me where you are going and how long you will be staying.