I would call them opportunistic, not scavengers. I watch them actively hunt very active prey like crawfish and aquatic insects all the time.
I have had good luck with a crawfish pattern and tiny (size 20) nymphs lately. They seem to eat a lot of small bugs, I was surprised to have 20 inch fish taking such small flies.
In some waters they are almost purely predators.
I have fallen in love with carp as I have started to study them and chose to try to master fly rodding for them.
It is odd to have a 6 or 7 pound fish seem small.