I've said this many times before...experimentation is completely natural and fine...but it is what it is and is only for so long. People find out if something really is for them or not... it happens a few times, a person moves one. In the other case, someone's sexuality is perhaps more or other than what they thought. You don't get to choose how you are orientated - opposite sex, same sex, or both. You do get to choose whether you will live your truth and embrace your authentic self, or not.
You try something, not for you, you move on. For these guys who keep engaging in it, seeking out, etc... even just having the feelings even though they may not act on them... then you are not straight. I don't get this whole "I may do this, may feel that... but I'm straight, dude"... uh, no you are not. Whether you act on it or not, if your feeling attraction and/or wanting and liking something of the same sex (physicality, emotion, etc.)... then you are not straight.
I think hanging onto every last ounce of heterosexuality for a lot of men is a huge thing to let go...