Let Plays and youtube?.

Hi. I have been wanting to do let Play on youtube but never had a decent video recorder to record gameplay footage. Recently Nvidia released the Shadow play and is really good for this. I started to test a couple of games and recorded about a minute of footage to see how fast it will upload and quality etc. I tested SimCity 5 and as soon as I uploaded it I got a warning saying Matched Third Party Content due to Music and could not post comments on youtube. I could do 3 things accept it, delete it or dispute it. But I just deleted and then could post comments again. But the thing is how do other people get away with it as there are other recordings with the same music on and even live plays?. I no you can put free music on from youtube but that's spoiling the lets play so how do trhese other people get away with it?. Also if I didn't delete or take action it could I have got done for copy right?.

How can I take this further with out disputing it as it shouldn't be ok for some people and is ok for others?.