They've said, I think publically, that they age the show up with their kids who are all about late high school, early college age. In terms of humor that is, which is also the average age of a mythical beast. I'm about 23 and discovered them when I was probably 13 or 14 from their Nerd vs Geek Rap Battle.

As far as I know though from my consistent watching throughout the years, as long as you're young as heart you can get a kick out of watching rhese guys. Younger kids might enjoy them for the gross content and watching them gag or do silly stuff, older kids/young adults probably watch because of the two's personality. They're unbeliveably funny to me, and I dont really have a problem with anything they do. Maybe that they seem interested in solely food content? But I can very much overlook that. I like the consistent formatting, I like the bits and gags, (i know some people have issues with some, CCR, Dirk and Patty, Moochelle (I loved today's moochelle content)). You could say that maybe they advertise their merch too much, but that's probably the #1 way they make their money so I cant blame them. They never overdo their advertising.

I think they hit a good sweet spot that they could milk for years, with a solid demographic of consistent watchers behind them. Branding it as, "a part of your daily routine," in the early days was genius because it likely created the backbone that they could spring off from.