If you care about rankings for non natty bound teams, you're an idiot. They mean nothing. It's just a way for parents and kids to brag to their friends and family about how great their kid is.
It depends how you use them. I have been on teams that use these to help schedule non league games later in the season, to find a competitive game. We've had a team cancel a game because there was a big variance in ranking and it would have been a blowout.
I have also seen tournaments use the ranking score to ensure teams enter in the right level. Some teams wont schedule non league until they come out, etc
But yes, some AAA teams use this as a bragging item and it gets out of hand