--We had Order pay the Zoners a visit once at O-74. It was part of an RP event and everything was organized. The moment the Order players entered Zoner Guard system, all hell broke loose.
Another example:
--A number of Zoners have contacted the Order to purchase Hathors. They got approved (TAZ for example). Now how do you enter O-100 to purchase a Hathor if your reputation with the Order Guard is not fixed.
The same thing can happen with Corsairs, IMG, etc. Special RP events happen where entering the Guard system is mandatory. Being neutral with all guards doesn't mean we want to be able to sneak into their territory. According to RP rules, you can only enter a Guard system with the permission of the respective faction's supervisors. That's exactly what the Consortium believes in and we discourage entering Guard systems without following through with this rule. But being white with all Guards prevents trouble from happening in the future.
Another thing is that you don't have to enter a Guard system to know your reputation status. Typically any sort of bribe with the non-Guard faction or 3 missions are enought to make your Guard rep neutral. Is performing missions for Oder and Military factions against Zoner RP? Yes, which is why I only take up the Zoner ID once my rep fixing is complete. The way I see it, most folks have to rep-fix one way or the other, and a lot of time it involves killing and bribing factions that you really shouldn't be.
EDIT: Let me ask you this question: Can you become a Zoner Guard without killing Zoners, GMG, Order, or destroying Zoner depots? And if the answer is "no," isn't that against Zoner RolePlay?