As for protective gear in itself : if an amateur would need to fight 4 or 5 matches to make it to the top in a national scale event would one let him do so without padding so as to have all the semi- and final bouts turned into abandons from smashed shins and broken ankles ? It is easy to say "learn them kick and block proper", much harder to do so. The long pants are a mess for legkick rules in any event because silk folds are causing awful shin cuts if there are no shinguards (the karate pants like those in kyokushin are made of a more rigid material and can't pinch the skin and tear it when a legcheck is done). So uniform is actually more or less a matter of adaptability to rules and less a matter of marketability. I know this will hurt some purists. I had personal discussions with top amateur organizations officials and all apart few advocated the use of ankle protections like the boots used in fc even in legkick rules, or at least of some shinguards covering ankle area too because after a dozen of legkicks thrown against opponents who make miss well and after the consecutive dozen hits ankle against calf the regular amateur will have his ankle smashed beyond repair let alone kicking elbows. With short pants it looks even more ridiculous yet it allows less damage to occurr.