Why are solicitations not allowed?

Recently there have been a spate of people posting in the Frontroom about forums in which they are members or moderators. However, they have promptly closed by either Beirut or BKS. Why may I ask? Some of the members may be interested in such forums and don't these fledgling sites have a right to attract new members? It is not as though it is advertising for certain products or anything. To me it just seems a bit petty minded: "Oh we won't let you have any of our members. These are our members and we will not let them go!".

I won't speak for BKS, but the one thread I locked was because the person said the link was one "I just came across the other day" and wanted to pass it on. I went to the site and saw that the person was a moderator there.

I don't want to accuse anyone of being less then honest, but I simply felt it was not... an appropriate way to link to another site.

The rules say no solicitations. The rules, of course, are open to question by the membership. Hence, this thread.

And we're not petty. Just very, very jealous.