I honestly think that this is the best way to tell most freelancers "we are an exclusive lot and we do not want you here". Globalization is to bring us together not to divide us. There are many other ways to collect money, improve your adverts or sell other things; but you can not tell people to go away if you invited them when PROZ was just a very small thing. Another thing is not to oblige them to buy a certain product (Trados for example, so that they can get jobs). Remember that most countries fought to get Freedom in all different ways.
I know this topic has been broached but is it really necessary to further marginalise non-paying members? This is I think aggressive marketing and whilst I fully sympathise with the founders for trying to get more people to pay to keep the site running and to make a profit, it is reaching the point of no return. Either pay or go elsewhere. That is the implicit message I am receiving each time one of these restricted jobs lands in my inbox.
Is this the message you are trying to send out?