Ok, gotcha. Not sure about the biological drive being unique to men. I'd say it is "human". But yeah, simply having variety could be one of any number of reasons for big numbers. Insecurity could also be a reason. Some men don't feel secure unless they are sleeping with someone. I wasn't trying to say that ego is the only reason, rather that the reason driving the high number may affect a future marraige if it's not dealt with. Like the guy who sleeps around to feel good about himself will not do well in marriage until he finds a way to feel good about himself without humping around.
Another reason may simply be opportunity. Based on what you posted earlier, being in a touring band creates opportunity. If its there, why not take it? I mean, rule number 1 for me in college was "if a girl wants to sick your dick, then let her suck your dick" (standards do apply, obviously
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