I'm trying to think of one it wasn't in? Oh, the Friday harbor one. Some of the contemporary romances don't have it - which is actually why I was reading those. The historicals are notorious for it.

And soap operas, evening or daytime seem to all do it...

I get that it is part of life, but ...

In most of the books it is used as a means for the hero to either save the heroine, to worry about the heroine's safety, to break them up, or make it difficult for them to have sex. Because of course, 90% of their relationship is sex. LOL!