??? my fighter? I'm the DM.
Speaking figuratively, "your fighter" being your fighter character within the group, whether you're DM or not.
And your last sentence is a bit insulting to quite a big portion of players, judging by the fact that the recent D&D variants (Pathfinder & 4e) both reduced the instant item destruction and were not selling all bad.
You are actually using sales to support your argument? So what about the D&DN playtest Medusa, how does that support your argument when SoD systems return? Or are you saying that removal of instant item destruction was the reason for 4E & Pathfinder's good sales?
And yes, rustmonsters potentially destroy the pace of an adventure with one bad roll.
More so than a crit on a character which kills him?
You cannot plan before how much and what equipment is destroyed.
You are not supposed to plan that much in advance anyways. And since
Rust Monsters are usually found in dungeons with other critters who do carry weapons the solution would be for PCs to go back and use the poor quality weapons against it, to protect their heirlooms and masterwork weapons and armour.
Saw a dwarf paladin (3e) pummeled to death after insisting to continue exploration after loosing his plate.
Yes and what am I supposed to say about that. I'm so sorry the foolish, foolish Paladin.

No dwarvern wisdom there.
You know what the most common wonderful solutions I saw in actual play against rustmonster? Wizards blocking the way raining down spells, monk hand chops and beating it to death with a club after a strip. Not very creative...
Sad. Next time, allow them intelligence checks to give them hints. Seriously they couldnt throw a couple of scrap equipment/rusty daggers at the monster one way, to distract it, and then rush past it as it moves away?
I'll give you an example of PC creativity from our campaign: I was DMing a group whose players were playing teenagers (no feats, no max abilities, no real equipment - nothing). They came across a bear in the woods, not fully grown, but still dangerous given their characters experience and powers. They only had a short sword between the 4 of them. So they formed a pyramid, climbed on each others backs (like cheerleaders), and pretended they were a creature who was greater in stature than the bear - they growled and howled and made threatening noises, and even threw stones/pebbles at it. They made a series of nature/intimidate checks and succeeded to ward off the bear.
I put that encounter in without any thought of how they were going to 'defeat' the bear. It felt realistic to throw the bear in the woods as an encounter and they came up with something great and on top of that they were pressed for time (they came up with that idea within seconds).
I cant see the big deal of using the
Rust Monster. It's a state of mind. If the players are rigid in their thinking and unimaginative, sometimes they need that int check for that DM hint, but to blame a
Rust Monster for poor roleplaying, thats just sad.
I might as well, what flavour you got?