No. It was simply tradition. She was from Eastern Europe, which was at the time very conservative with these matters. And it still is today I believe. She would talk to us, her friends, but not to her boyfriend. Each time we asked her why doesn't she do it, her reply was that "it wasn't lady-like for a woman to propose to a man" and refused to elaborate further. Basically she consciously or unconsciously conformed to gender roles. We debated inside our circle if one of us should talk to him about this, but we decided against it because if she were to find out we interfered she most certainly would have been angry about it. He finally proposed to her on his own.
About the dropping hints thing. I myself have been fortune to have had straight talks about potential relationships with both my now ex-wife and my current partner. But some of my friends didn't have this luck. And some of my younger friends, both males and females, suffer from social anxiety. They could be head over heels over eachother but would rather run away than talk about it.
If you have a mixed gender group of friends it's easier to see who is into you and who is not. But if you approach someone new, it's always a chance that you might creep them out. Again, excluding the obvious assholes this post is referring to. I know of some couples who are now happily married and started out with him approaching her, but the asking for a phone number came last after they have interacted the whole night. For example we had a guy that actually lost a bet and we made him go ask a colleague out. They married in 2012. But that's a happy story.