I think I may finally have a grasp as to why the Japanese require a license to get large quantities of H202 or would otherwise look at you funny if you tried to buy large sums of it ... thanks torecent news stories, evidently common over-the-counter H202 is a standard ingredient along with acetone, common in nail polish remover, to make a fairly potent bomb. I can certainly see countries more exposed to such acts would be more restrictive with such common chemicals, in much the same way chemical fertilizers are closely monitored in the US (and most likely elsewhere).
So somebody walking out the door with a few cases full of H202 to de-yellow their Macs would very likely be the recipient of some reasonable suspicions, especially if they had the misfortune to be picking up a few bottles of nail-polish remover for their wife ... sad state of things.