I've been using various Internet chat thingys since 1987 or so. Most of the free ones (including one of the most popular, IRC) have ended up with major hacking/abuse problems of various sorts. I currently use one that's pretty stable, but only because it's relatively obscure.

As another example, look at the game servers (chess and backgammon are the ones I'm most familiar with). The pay services suffer much less frequently from the typical problems (deliberately dropped games, people playing with the help of a program, rating stealing, spam) than the free ones.

Pay-for message boards are the same way as well. Even a $5 yearly fee can make the difference between incessant spam/flamage and reasonably coherent conversation.

That's not to say people can't steal credit cards and accounts in order to abuse a chat system or whatever--but it takes more motivation and planning. Most of the IRC stunts are conducted by bored kids; if it's too easy and costs nothing, people will do it.

I can't comment on the "appropriate behavior" or "safe environment" stuff, as I suspect the desperate people are "lewd" whether they have to pay for the service or not. I do believe that requiring a subscription of some sort will cut down on much of the abuse.

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