You've already explained your videos violated music copyrights, so why ask why your accounts were banned? Answer is already there.
Maybe search around for Creative Commons music you can use.
Legal Music For Videos - Creative Commons
__________________
WP Porn directory/review theme
Maddos $35.
Demo
WP
Adult Video Checker $20
Import vids into WordPress from PornHub, xHamster, YouPorn and lots more =>
VIDEO PORNSTER $20
webmaster AT howling-wulf.com