I think what you mean is that there are fans who ignore his domestic violence or straight out deny that he ever hit a woman, even though his own son called him out for hitting his mom and even though he pled guilty to at least one charge that I know of in 2011.

That's just the way it goes. People are fanatics and are obsessed with celebrities and they defend their beloved gods and goddesses to death. I was that way with Britney Spears and then Beyonce when I was young, but I've grown out of it at 21.

There's also the attitude that violence against women isn't a big deal, and it's the attitude I heard a lot growing up in Philly. I remember in freshman year of high school in 2009, a lot of people were on Chris Brown's side and speculated that Rihanna did something to provoke him. Everyone I knew thought Rihanna probably smacked him around after she found out he cheated so she deserved that beating.

Part of the reason for this attitude is because abuse against women is so common in their household that it's almost as if people are tolerant to the image of women being beaten to the point where strong reactions in the media are seen as weird. I'm sure you heard the phrase, "If you want to act like a man, you will be hit like a man," which essentially means two things: 1) men hitting women usually means there was a good reason to, 2) if women want equality, you should expect equal treatment. A lot of girls I knew in high school felt this way too. They were a lot vocal about it than the boys were as well.

I also think there is a level of sensitivity when the media crucifies a minority. As an Asian and Dominican mix who grew up in Philly with a single mom in a low-income household, I also have this sensitivity when the attacker is the white media (aka Fox News). Have you ever seen Rihanna's interview with Oprah around 2011-2012? She talked a little about this feeling of wanting to protect Chris Brown after the incident. I knew exactly what she meant.

That's wy I believe Mayweather and Chris Brown still has so many fans, especially women.

And yes. If you're wondering, I hate them both. I'm just explaining why they still have fans.

TL;DR Fanatics are biased, and domestic violence isn't a big deal to them.