ty33:
I agree, but only for the same exact ball for in real golf you cant change out for a different one in the same round
Under the rules of golf, you cannot switch from one ball to another of any kind during a single hole except in certain circumstances, e.g. the ball is lost or damaged. The next ball you put into play on that hole can be any conforming legal golf ball.
When you start the next hole, you can tee off with a different ball if you wish--any conforming ball.
It is only under the one ball condition that players must use the same type of ball throughout the round. Then, if a ball is lost or damaged, they have to put another ball into play that is the same type of ball.
The one ball condition is not an inherent part of the rules of golf, but it may be imposed by the organizers of a specific tournament or the like. WGT imposes the one ball condition, so that is why a lost or damaged (worn out) ball may be replaced only by one of the same type.
The official list of conforming balls lists balls of the same model but different colors as different balls, so that is why WGT treats them as different balls. A little absurd, but there you have it.
However, there is no justification under the rules of golf or the one ball condition for treating two balls of the same model and the same color as different balls simply because one of them is a vapor ball and one of them is not. This is because in real golf, conforming balls do not leave vapor trails.