The fact is that the cheats are enabled by the custom firmware, even if there are theoretical ways to accomplish it also. The problem, as usual, is the will to cheat. In practical terms in this case, disallowing the custom FW by coded file-locking and/or encryption would disallow the cheating done by the currently available method. Deal with that first. If another cheating method is later implemented despite its being more difficult and unlikely to occur than the one currently in use, then dealing with it can be attempted in its own time. The important thing is to stop the cheating now. It is useless to blame cheating on those who did nor foresee better how the weaknesses would be abused, but it is up to them to seek the cure and to implement it.