I believe I know what you mean. Just enjoy it. They do it for entertainment value, so others can enjoy their work. I'm a huge fan of Buono!, & I don't care who knows it tbh. Maybe it's because I'm around the same age as Miyabi, Momoko & Airi (I'm 19), but I enjoy their PV's & songs. Just enjoy AKB48. & the fact you feel guilty about some of the MV's, is good. It shows your not one of those nutters into all that underage business