Givemewings
It's not an issue, but I think you're trying to make it into one! If the Captain accepts visits after or even before the flight, so be it. They're the Captain. They are in charge of the aircraft and wholly responsible for they're actions. They are not some 21 year old fresh out of college so please show some respect for the position and experience they hold.
I assume you're cabin crew, right? It's not a safety issue so just do as he says. He's the one who has to answer for his decisions, not you. As for another of your comments, I think you'll find the vast majority of guys posting on this thread have no objection to visits on the ground.... even A380-800 Driver....I think!
Harry