>>56246589I'd imagine hitmonlee was an earlier inclusion that they bit off more than they could chew with, thus the excess moves nobody else got.
On the other hand, it's probable no other mons needed kick moves, so they had too low of a variety already planned, which would of course ruin Hitmonlee's gimmick. So they *had* to make special new ones, because they otherwise didn't exist, and otherwise its design wouldn't have translated mechanically.