It's the old community vs market argument.
There are people (and I am one of them) who like to think of places like this, where people who have a common interest gather, are proper communities. Within these communities there is perhaps an idealistic expectation that the members will act with the community interests at heart. It is always a disappointment when you see something that falls short of that. Even when there is no legal basis for complaint, the community ideal has been offended.
But we live in a market driven world and that will invade all places where there are transactions taking place. The hope is that they don't happen often enough to damage community spirit, and if they do then the community should try to take steps to reduce the problem.
I've not been a member here long, but I have seen some great community spirit displayed by some members, I have also seen some less charitable behaviour! Let's just hope the good continues to outweigh the bad.