I found something interesting that happens when you use the "multi item" hack. When you use it to just increase a characters level to 6 after lets say you buy it from the store or pull from a pipe. Now the game shows for a brief moment a value of 999. I found that strange because before version 1.6 and down I did not see this occur at least from what I can recall.
Something about that tells me that nintendo added this feature because internally in the game it allows them to keep record of this value. So when they do an assessment of accounts and they find that the characters we upgraded have an unreasonable level of increase it will set off an alarm. We can't see it but they can.
Just like having 99,999,999 coins or 9999 tickets can get you banned I believe this can get you banned as well if the value of 999 for the characters level gets saved internally.
I think nintendo is just not giving us any options to save any progress with these cheats. Even if you try to go with the conservative approach and get only 100 tickets max from each. The unlimited tickets hack does not work so this wont be possible either.
I wish the unlimited tickets at least worked.