1. The evidence for the roots of 'Blackface' are in Minstrelsey wich was racist.
The counter evidence, possibly more compelling, when you consider the whole nature of morris is that it was a means of disguise, as recorded in the 18th century, and not just border morris, but molly dancers in East Anglia.

2. Most Border sides make up the dances, the kit, the tunes and play instruments never heard in Morris - great drama has been created - please stop blacking up.
There are only a few recorded dances from the borders, and morris sides creating their own is part of the living tradition, and as pointed out before, painting faces is merely part of the kit.