I think things are a little different here. For dressage, black girths are the norm, and leather girths are, well I'm looking at the Dover catalog. There are some brown fabric ones, have yet to see a leather one. So it's hard to go all matchy matchy. Heck, I don't even see a white girth except the string ones. I have a tendency to stay away from fashions... they come and go and just cost me more money than their worth.
If your horse says no, you either asked the wrong question or asked the question wrong
And God took a handful of southerly wind, blew His breath over it and created the horse