kitov,
Can a individual benefit from remaining single ?
Yes – in almost any situation there are benefits and downsides. Decision making usually involves attempts to maximize benefits and minimize risks and downsides. I happen to feel that there are far fewer benefits and far more downsides to being single than there are to be married.
Can a family benefit from a single family member ?
Perhaps, but is it wise for a person to remain single (and not start his own family) because it benefits the families of his relatives?
Can the Orthodox Jewish community gain from a large single population ?
Sure. The community also gains from growing families.