Well, if she is in fact a wife, then one would hope that the kind of relationship she is involved in would be one where mutual respect is an issue. That being said she would have talked to her husband and they would have agreed that is was acceptable for her to do what most folks would consider an act of betrayal. In that regard I see absolutely nothing bogoted about what the guy said.
If my wife did something with another guy against my wishes her ass would be gone, period. Being that I like her with other guys and we have talked about it, she is ALLOWED to do so. There is no bigotry at all in that statement.
I think you are being overly sensitive. If you want to tackle bigotry as an issue there are TONS of other posts on this forum that reek of it. In fact, one could argue the specialty of this site, married women cucking their husbands with black men because of some preconceived myth, is in fact bigotry. Still, I think you should just relax dude.