Gyuki: Don't decide who's strongest because of the number of tails. Later... Kurama: So what was that about deciding who's strongest? My Jinchuuriki just bodied five of our siblings with half my power.
Probably to do with copyright issues and stuff, if they don't cut it it'll get taken down, and presumably having other content in the middle makes it even less likely to get taken down. Or they just thought the dubstep was cool and threw it in to make a "cool" edit