AC/DC, Fight Night, and the Promoter

So I joined my brother tonight and went to an International Kickboxing Fight Night thingy...not really my scene, but interesting none the less. Interesting because the first few songs that I heard at the event were all AC/DC. This got me thinking. At what point will AC/DC not be played at fight nights, or other sporting events? You could tell the promoter for the event was in his forties or fifties, and loving the music, so my question is this;

Twenty or thirty years from now, when our generation is putting on events, are they going to still be playing AC/DC and Black Sabbath, or are we going to be playing 30 year old music from then, like Lincoln Park?!

Not that I consider Lincoln Park to be the 'new' AC/DC, but at what point are they no longer equated with the fight song? Twenty years from now, will listening to Sabbath at an MMA fight seem like putting on the Beach Boys before Boxing? Anyways, just a thought. Oh and they actually did end up playing Lincoln Park half way through the night, and yes, one of the dudes in the picture was also there, seriously, haha.