As much as I prefer to buy and sell coral from people vs. stores, this thread is the exact reason I shy away from it. Everyone has their own preferences. I don't like to inconvenience people. I have had people that show up and ask a million questions when I am busy and have other things to do. I have had people ask for a bagged up coral at the door because they were busy. I normally call when I leave and let people know when I am close. I usually tell them on the phone that I am okay with them bagging up the coral. I know other people that want to see the tank before they buy.
I don't know how many times I have waited around for someone who is rude enough not to let me know they changed their mind and were no longer interested.
This is the exact reason that true hobbyist swaps are the best solution. This is why it is so sad that most swaps have turned into a money making venture for vendors. Sure anyone selling corals is looking to make money to put back into the hobby. Sadly, at most swaps I have been to, the same hobbyist that I think should be supported, ends up as the guy sitting in the corner not making any sales because he doesn't have a fancy setup or he doesn't know the name of his corals. I do like seeing the CR group putting together their own mini cookouts with this exact goal.
One last thing - As a homeowner, if someone is doing something that you don't like, most of the time all you need to do is ask. I normally walk around with shoes on in my house - I am a weird person that just likes how shoes feel. I am aware that others don't because I worked a job where I entered homes every day - some may have not. Asking for courtesy goes both ways, people are typically non-confrontational until they get onto the internet. The people whose kids run all over your house are probably so busy checking out your tank that they don't even notice. Or they are laid back and that is not an issue with them normally - a simple comment about your kid is going into the other room would probably be enough to have a parent realize and reel their child back in.
Everybody has a different tolerance for things - its what makes us human. I don't know many people that are successful enough in their day to day life to afford a reef tank, that do not have the skills to be courteous. The average person with a saltwater tank is a pretty responsible person - these things are a lot of work!