I'd like to just add a point that hasn't been touched on I don't think, though all the above is pretty much spot on as well.
Consider for a moment taking a blade-less sword, just the hilt and how quickly it could be wielded with no weight in the blade itself. Now attach the deadly light saber to it, you can move it so quickly that I would argue in a real fight it would be quite deadly to a non jedi opponents in close combat, but very deadly to the user as well. One wrong reflexive twitch and you cut yourself wide open. It would be like wielding a real sword, to an extent, but never so much as touching any edge of the blade even lightly, sharp side or not. The jedi have situational awareness of exactly where the hilt is pointing, and where it is going next, it would be very deadly to the user if you didn't have that awareness. Basically part of its amazingness, the combination of quick and deadly, the ability to maneuver it almost instantly with the flick of a wrist, is what also makes it to easy to hurt yourself with and too impractical for non jedi.
It has a far too high expense to usefulness ratio to be practical for everyone even a well off fighter to carry I would think. That being said, given no other option in close combat, should it come to that, if a light saber were nearby and available, I would certainly expect that anyone would attempt to use it with no other weapon available, likely even over conventional close weapons.
In season 1 or early season 2 of the clone wars, princess <PERSON> is taken hostage with some other senators and happens to have <PERSON>'s lightsaber. 477
She poses to another senator whether she should use it should she need to. I think this scenario is very realistic, it is still a devastating option in close combat, but it is more useful in situations like this where you wouldn't ideally find yourself as a non jedi in the first place. Non jedi are going to spend their efforts not being put in a situation where a lightsaber would ever be useful. Just like today's war forces, or even home protection, you never want to be close enough to come to blows with the opponent ideally.
Also, while the movies and such focus on activities surrounding jedi, keep in mind that jedi are extremely rare (I seem to recall reading somewhere at the height of the council, there were around 10,000 known jedis, and estimates figured ten times that many unknown, so 110,000 out of trillions of being force attuned, and 10,000 out of trillions that actually practice). The odds of coming across that kind of weapon, or having to defend against it are quite rare in reality, and even if you had to defend against it, you aren't going to beat a jedi in a lightsaber dual, fighting fire with fire does not hold here for non jedi.
One unlikely scenario.... If for some reason the price went down and proliferation of lightsabers went up, like say if an army decided it would/could equip all it soldier with lightsabers, and it made tactical advantage to do so, then you'd suddenly see an increase in the use by everyone else so that they had some sort of close combat defense against it. You'd also likely see unintentional self inflicted casualties rise in said armies! 347