That's actually pretty representative of the people I see drinking Monster drinks.
This doesn't imply that people in higher income brackets don't drink it, even most of them (though probably untrue).
Also pertinent is that the data is specified for Monster Green, which is their full sugar product. Monster Zero is a pretty big product as well, and could have a slightly differing customer base.
Just want to add that all Monster (AFAIK) contains sucralose even if it also has HFCS or other sugar. It's a small amount because it's so potent, so I usually start at the end of the ingredients label when checking if drinks have it. NOS also puts it in their regular drinks. I don't know when they made this change, but I stopped drinking Monster because of it. I used to like the Mean Bean Java Monster quite a bit.
My energy drink of choice these days is Blueberry Red Bull, in case anyone else is looking for an option that tastes better.
Also some brands like Rockstar put it in half their flavors, so you gotta check every can. Even though Killer Citrus is safe (as of 5+ years ago when I last looked anyway), Killer Grape isn't, despite both being of a similar subtype.
From another angle, I think it's quite shady and dishonest of them to mix artificial sweeteners into non-diet drinks and not make it clear. If someone sells sugar free drinks and not-sugar-free drinks, they shouldn't both have sucralose.
I have heard certain artificial sweeteners kill your gut bacteria, but honestly I don't care much about that. If I heard that about sugar, I wouldn't start avoiding sugar.
The green monsters are definitely more male gamer oriented, but the white, green, pink, rose monsters etc seem pretty popular with people in my generation who fall outside that male gamer demographic.
Personally I prefer red bull now but as I get older I mostly drink coffee.