The expectation is that the SD (where feasible) is to welcome the SE/MM's on board when seated in Y/C.
On occasion, there are F/A's on board who take a peek at the final flight manifest and ask "Who are my SE's in the back"? I simply assume it's their way of giving an extra TLC to our most valued customers.
The drink-in-the-exit-row scenario? Outlined perk - no. Nice gesture - yes