Basically, don't ever push the call button.
Flying home Friday night on DL between CVG and ATL, I was seated in F next to a pilot (probably Comair, but not in uniform) and was enjoying the conversation. I was parched and pushed the FA call button to request another bottled water. A FA came by and stared at me wordlessly. I nicely asked if I could trade my empty for a full bottle. A moment later, she came back with 2 full bottles and took my empty. Again, no words escaped her lips. The pilot looked at me a little funny and we continued talking.
Saturday morning, coincidently, I'm reading the last Budget Travel magazine and come upon an article, "Journal of a FA", or something similar which is a Q&A interview with an anonymous FA. The headline reads, "Basically, don't ever push the call button" and her A to the Q expresses how annoyed she is when someone pushes the button ... usually to pick up trash right after she's passed through the aisle 6 times.
I did not feel like I did anything wrong, but the look and silent treatment told me I had, in her eyes. Next time, should I go to the galley and help myself?