It's not as strange as you might think. In the NL, teams don't need to be encouraged to use British riders, as that's pretty much (Barring a couple of Aussies) all they can use. Having the reduction would pretty much defeat the point, as 99% of riders would be getting it. However, moving into the PL, you can have anyone. This is where it is needed, as teams don't have to use the British rider.
At least, that's how I always looked at it!