On Long-Distance Relationships

People in relationships are fascinating to watch. I've seen some people move lately, and start up "long distance relationships" with their partners.

Why these people maintain their relationships like this makes no sense to me. Logically, they could find another person capable of giving them the same or more as the other person, but who is closer to their present location. Are they too lazy to contribute the effort required in finding their next partner?

For whatever reason (laziness and fear of change even in a changing environment is my bet) they don't do the sensible thing and call it all off. Instead they put themselves through what appears to be considerable amounts of loneliness and pain just for a few moments of expressed "happiness" when they briefly reunite, and then more pain and sadness that follows when circumstances naturally separate them again.

Nothing is inherently special about themselves or their partner. Why not just find one of the many other potential partners? People in relationships need to learn when to cut their losses and maximise their gains. If a long distance relationship becomes the most beneficial relationship possible, it's a sure sign you've found yourself in one of those situations.

Inwardly I have to laugh at the people who do this. I know better than to be so "harsh" as to point out what is painfully apparent, so I play along and listen to their depressed ramblings. I even try and provide comfort when I can (maybe they just like the attention it gets them?), as is dictated by the rules of society. After all, those rules are what allow me to keep them my friends and not make them enemies.

So to recap I don't understand why they say they feel so sad about maintaining the long distance relationship, I don't understand why they insist on complaining so much about maintaining something in their control to end, and I don't understand at all why they don't just find some other person with whom they can drop the "long distance" from that term. I find it staggering they keep the relationship going long after being capable of keeping input vs output balanced has been clearly thrown out of the window...

I am curious to see what comes of their self-imposed suffering and wish I could ask them what makes it worth it in an honest setting, where I wouldn't risk losing their friendship by talking like the "heartless bastard" I am inside. If another person can give you more, or the current person is giving you nothing near enough, why stay with what you have?