It pains me to say this, but I agree with Bennys no.2 point.
If they paid holding the balls (the ones that should be paid, but aren't anymore) players will have to vacate the immediate area so the player can take his kick. Letting him hold onto it, then call a ball up just causes everyone to congregate in same area, and most ball ups result in another stoppage immediately after.
Pay the frees that are there, and the game will flow. They don't call them either way. They let the player being tackled drop the ball. Once the ball hits the ground, of course everyone's gonna jump on it if they haven't heard a whistle.
Boundary umpires and field umpires also contribute to congestion with the throw ins and bounce ups. They continually look over their shoulders and wait for people to get to the impact zone. Don't wait for the players and they will learn pretty quick. It will probably lead to less off the ball free kicks.