Which ones? I thought all those businesses vanished. There are still some left-over users from those pay-for sites using the network.
I guess there will always be those same type who advertise free downloads & then shift to another site a while later. That's how some of them operated when the heat was onto them; Grab & run.

I've kinda given up on looking for new gnutella based applications.

But when I did run into something like that (if memory serves correctly) they'd offer a free version and a pro (buy) version.