Being a member doesn't mean you have to come here more often, hilary; and if you don't want personal messages, just don't open them up. All right you might get curious -"you have 15 active messages" - hard to resist having a quick look.
But it's handy being able to put a trace on a threread you're interested, and there's other useful features.
And it means noone else is ever going to be able to post in your name (unless they sneak into your computer of course).
Mudcat addiction, for all we joke about it, is potentially a real problem. But I can't see how it makes any difference whether you're a member or not.
I don't think making it members only would eliminate the sort of non-members we'd be better off without. All you need to register is to have an email address, and you can get them as easy as writing on a wall. A membership only policy could well end up making it worse - and as has been pointed out, for all the occasional crap, this is a pretty good set-up we've got here.
Maybe the only people we'd lose with members only would be the people dipping their toe in the water because they just think they might like this kind of music, and we don't want to lose them. And we'd probably also lose some non-member-members like hilary.
Anyway, it's not going to happen, because the good guys in charge won't have it. This ain't no bourgeois democracy, after all!