They are made to be part of the price of the bike that was affordable, as a whole..
Above that , the engineers , added the features, 9th , and 10th cog in the cassette, the levers to match those closer
spaced selector notches in the Brifter.
Retroshift puts a lever to shift with on the front of a different brake lever.. you might be able to find the previous
8 speed bar end lever, the working part of that is to go on the front of the brake, lever mount.