It's not WGT's responsibility to provide substitutions or an order of substitution when balls run out. The rule they enforce is the rule in this game. It's their game design; they can do what they want (or not do what they can't or won't).
The main problem still comes back to a WGT lack of effective communication. The one attempt at explaining it from their end involved simulating the One Ball Rule, which does not apply to club level tournament play, social games that count for handicap purposes and especially practice rounds. That WGT explanation simply doesn't work. I would much rather have a moderator step in and say that they can't make the rule more realistic it at this time with the programming they have in place. And point out they simply have too many higher priority issues they're working on.
WGT used that explanation a long time ago to explain the inability to split up iron sets to take out some irons and replace them with more wedges and hybrids. The programming didn't allow it and they weren't going to attempt it. End of story. It doesn't mean it won't happen a year or two or ten in the future but not now. No reason to even argue or discuss it right now. That pretty well stopped the threads.
Instead we get silence from WGT and constant arguments between members regarding ball substitution. WGT should weigh in with an effective statement and shut the arguments down one way or the other. Is someone eventually going to look at the programming to see if it can be done in the future or not?
BTW, the PGA and USGA established by precedent that a different color of the exact same ball with no other attribute changes counts as the same ball under the One Ball Rule. When Nike introduced the Nike One Black years ago the players promoting it were able to use the white version on par fours and par fives while using the black version on par threes.