FV and MDT, it seems that you havent been around the block to long?
Lycan is quite right on saying that it make the bike much more visible to other road users.
During day driving, even with your headlight on, the light blends in.
You wanna be much more visible to oncoming vehicles. Thus the orange covers. More visible to others, the more you stay safer, the longer you live to tell your kids bed time stories.
Or now these days, LED spots seem to add more attention.