Behaviour like this isn't the sign of anyone crazy. Arguablely it is the sign of someone very smart. He does it because he can. Stirring up silly little things like this is a great way to remind the populace who calls the shots.

From the technical/IT side of things it is trivial in the extreme. Any useful operating system takes this in its stride, they all use Olson's zoneinfo code, measure time internally in UTC, and can cope with any time-zone offset, including those counties that are on arbitrary offsets from UTC. And it copes with arbitrary changes in daylight saving and time offsets in its stride. Of course there is one OS that is so inward looking that it fails to cope with such trivial things, but no-one technically literate uses it anyway.

As noted there are a number of other areas of the world that live on half hour boundaries. I live in another. It is a pain somethings, mostly because pretty well any watch you can buy has a really easy jump hour adjust capability, but changing a half hour means you have to drive the minute hand about. So travel means you have to spend an extra 30 seconds messing with your watch. Other than that I don't think I have ever noticed.

Up until nations were linked internally by railways each town would typically set its time to the appropriate time as befitted their longitude. The UK set the pace, most railways had standardised on the one national time by 1847. In 1880 the legal system followed suit. Of course since it also defined GMT, the UK was by definition on an integral multiple of an hour offset. Where the multiplier was zero.