Just because you are friends doesn't mean there isn't sexual tension

Ya you're right I can't have girl best friend lol, it would be weird in a way. Or maybe if she was no attractive?

If they are getting sex from elsewhere, there won't be any tension.

This. 

I approached every girl I've ever liked because they were attractive, or I liked them as more than a friend because they were attractive. If I don't find a girl attractive, and I don't want to be intimate with her, she is a friend.

So no.

I've always had girls as friends, but most have been like girlfriend's friends, so they were off limits anyway. And with every at least mildly attractive friend thats a girl I've had I've thought about banging them at one point, so as a straight male, it's hard to have platonic girl-boy friendships with girls who aren't unnattractive. 

False. I have many friends of the opposite sex and while it's mostly very relaxed, with some of them there are quite often moments of sexual tension. It can be fun and it can be annoying, but it's there.

Without the drive of sex it would just be a close friendship, I think.

That works both ways. If you have a long relationship, the sex can get boring at times and you need something else to keep you together.

OT: There would still be relationships. There are actually couples who have relationships without sex. They're just asexual, but the desire for closeness to a fellow human being is still present.

This is obviously an opinion between different people as you can see from this thread.

No definetly not. Why would I do something like shopping or why should buy expensive clothes and shave frequently if not to impress or seduce the other sex.

You talking to me?