As one of the individuals who wouldn't even be invited to participate, I feel that I ought to chime in.
The last print exchange I participated in was a lot of work for me; and I enjoyed it thoroughly. I agonised for weeks over what print I would send out, and then I played with the print numerous times in the darkroom before I had something I would be pleased to put my name to. Not because I make stellar prints or anything, but because I put in my best effort. For the first time, I wasn't just making a print for myself, but was actually 'forced' into a situation where others would judge my work.
Then there were the constructive comments. Papagene even took the time to drop me a note to tell me how much he enjoyed the print and that I ought not be afraid to take the plunge and try FB paper next time. Well, thanks to him, I have tried FB paper and will use it in the next print exchange. I also received some gorgeous prints, which allowed me to see what photographers with a great deal of talent are doing.
All in all, being able to participate in a print exchange with photographers who are far and away superior to me allowed me to learn something; for that I'm very grateful for the print exchange as it is.