My DM (who posts here often) recent threw a player out of the game forever for slamming down a minature! He's very protective of them.
(Well, she also threw temper tantrums when her character failed at something... but the miniature slamming was the straw that broke the camel's back...)
I just cut out squares of paper for most adversaries in battle. Makes it easy when fighting a monster or something bigger than a single 1 inch square: just cut out a bigger piece of paper. Cheaper and easier to deal with, plus they interact with the actual minis (the PCs) with no problems....
WHen we play Star wars We use my friend's Star wars Legos for minis. It very fun. My friend is a big Star Wars Lego collector He even has the rare Mellenium Falcon Lego set.
Actually, my players, even though none of them are miniature painters (all have their unpainted 3000 point Warhammer armies, though) have respect for the craft and the time and effort that goes into it. Thus, I've had no big problems.
I did yell at that one high elf player for disrespecting Vadania, though.
Some people have absolutely no respect for other people's property.
I tell people not to knock them over, not to bang them together, not to clump them in a lump in their hands, and so on.
But they seem incapable of treating them well.
If I did any of that to their dishes or coffee mugs when I visited their houses I'd be out the door in seconds...
It really annoys me. Even more so that I have to keep bringing it up and keep getting ignored. Or get a nod and then proven not less than 10 minutes later that they weren't paying me any attention...
Do you gloss coat your minis? It adds a protective layer to make them more idiot-proof, and I think it a must if you intend to game with them in any way.
We use those coloured lumps of glass instead of minis. Hell of a lot cheaper, still pretty to look at, can represent anything, and much much harder to damage...