Sure, it's not the only reason we watch. Of course there are other reasons we watch. We await anxiously each longing gaze, each tender glance, each enchanted smile, and we smile right along with them when, at last, the creators get it all right. Not that it ever lasts long. Story arcs lead to ratings points.
Ratings points lead to future episodes.
And no one knows the best application of this complicated formula better than one Mr. Joss Whedon. It has often been observed that sex in the Buffy -verse always leads to badness, and that is none the less true for having been plagiarized from a million different sources. In fact, twice. If that's not badness right there, then I don't know what is. So, in Buffy , sex, like beer, is bad.