They are black. No worries.
Anyway the point is simple. It's for attention. It's a specific, seemingly random design choice right? It was made up by a certain band of Cosplayers to obtain more attention for their work. It makes them appear "in the know" & it provides more opportunities for these people to make a living out of playing dress up, or obtain connections. Along with other perks like feeling important and popular.
Many cosplayers have done this before. This isn't a case of pointing fingers, its an actual method they use. Its only ever "their word". They will typically reply with "no comment" or "I can't comment on that". It's a simple ploy, that usually goes over pretty well. thats all.
The last people you should ever trust concerning films and the BTS details, are cosplayers. Even the man in the picture above (Jordan Chapman, crossing his arms) has been caught in several lies before concerning this very film.
Lujho, your the man haha. I've briefly explained why some people are more sour than others. We have been burnt before by these kind of people and if it were an honest mistake, then I would totally agree with you!