I find it astonishing that so many Mudcatters cannot accept that its perfectly possible to COPY something without MOCKING it.
I take part in re-enactments of Napoleonic era battles, and as such I wear the appropriate uniforms and affect as far as I can the speech and mannerisms of the period, Am I mocking soldiers of the Era ?,
I also formerly played in a country and western style band, and when on stage I wore Stetson, jeans, checked or fancy shirts and cowboy boots, and tried to use an American Accent when singing, am I mocking American Cowboys ?? certainly in neither case was I trying to mock or insult anyone.
I don't find it beyond possibility that 19th century white performers seeing the popularity of the black colleagues on the vaudeville circuit decided to try and emulate their success, and adopted black make up as part of the act, I don't think we can automatically assume Evil intent in this. !!
By the same token Morris dancers of that period in some areas may have built on an already existing tradition of disguise in order to appeal to a wider audience by incorporating elements of the then popular minstrel acts in their performance. The Photo of the American team in there "Kiss" style outfits shows this still happening today.( Or are they Mocking Kiss !!!)