No. Sexuality is a sliding scale; which means that yes, there will be people on the far ends of the spectrum. And it's not a bell curve either with 'most' people falling in the middle. I'd picture more of something like this completely unscientific graph:
I saw an actual graph years ago... and it seems to suggest that indeed the peaks were at the edges (0 and 1 and 6 and 7)... but it's interesting that the the numbers of 2s and 4s were much higher than 3s and 4s and 5s were more prevalent than 2s.
So, it suggests that people are mostly straight, but a mix of various kinds of 'queer' along the scale but with 3s (absolute equal bi) being the smallest representation.