Does the fact that Buddha-ists are too shy to promote their "religion" indicate their own hesitation toward it?

Nope it's our way of letting people find their own path which is what Buddhism is all about. If they are interested and want to learn more fine, if not fine. It's up to them. Don't get me wrong if someone asks me questions I answer but I'm intelligent and respectful enough to let people decide what they want to believe. They are going to anyway. Me shoving something down someone's throat isn't going to make anyone believe anything. It's just going to upset them adn make them mad. PLUS, it wouldn't be the Buddhist way.