At least in New York City, I think much of the problem stems from the actual language used to define skill level.
In New York, players are typically rated as Pro, Open, A, B, C and D. This creates a very interesting scenario since Open players are not considered professionals and yet they fall outside the "letter spectrum". The value of A, the way it's typically defined in society is huge here. When is "A" not the best? Only in pool is "A" trumped by "O" but is it?
I think, for the most part, people consider "A" to be top amateur rank when in fact, the Open class is. Because the Open class is seperated from the letter spectrum, they default to professional events. They're amateurs who are not allowed to compete with lower-ranked amateurs.
If the amateur spectrum were to encompass the Open class, or in other words, Old Open=A, Old A=B, etc., I think most amateur players and organizations would be more inclusive. Until that day passes, I think there will forever be pool purgatory, especially in New York City.
I could be wrong, but i think Open and Pro are "new" designations around NYC. Im fairly sure it used to be A, B, and C only. When the Tri State tour began Ginky, Frankie and the like were A Players. Johnny B, Gypsy, Joey Kong etc were 'B' players. Something happened like Ginky winning too many maybe and the Open class was created. In the shake-up most C's became B's, B's became A's etc. Then after some more complaints the 'pro' class was added. Sounds crazy-im unconvincing myself as i type.