Do we have any concrete proof that he's been using real eggs and hasn't replicated them for the sake of preparing them 'the old fashion way'?
Riker states that he picked up the oversized eggs on a planet they had recently visited, the implication is that they're real (out of a living beast) as opposed to replicated.
the term 'real' is very inappropriate here because replicated food is just as real as the original.
I'm using real
as in natural, and then replicated
to mean artificial or facsimile.
Probably not. If you order a replicator to produce a T-bone steak, it's unlikely to biologically be a piece of bovine muscle tissue attached to a segment of vertebra. not at the cellular level, it's just a facsimile.
If you ordered your steak "fresh tartare" (right out of the cow), and applied a electrical charge, the replicated meat probably wouldn't move like a "real' fresh cut would. Doctor Pulaski couldn't create a new Human heart for Picard because the replicator couldn't do it.