From recent expeiences with crumbs and the such being embedded into the carpet fibers on aircraft floors....
Why is carpet used at all?
Why not an easy to clean vinyl?
Or even an good coat of an epoxy-based paint over the existing sub-floor?
I'd think that the paint would be a substansial weight savings over the carpet. And, an epoxy-based paint would be water-proof and help prevent corrosion (due to spilled drinks, etc...).
And, the vinyl or paint would be really really easy to see and clean the crumbs.