Scene: entrance to Multnomah County Central Library in downtown Portland, near closing time. I'm leaving, and once I'm outside the door I hold it open for multiple people. Maybe about eight. No one says "Thank you" or nods or otherwise acknowledges. I wait until I can close it without closing it in anyone else's face, then swing my arms out wide, and say "You're ALLLLLL welcome!"
At least one guy smiles at that. Smiling, I say to him, "that was strangely satisfying."