Who the Heck makes this stuff?

[dyslexicfaser]

How about a wizard with a high Int but a low Wis? He could easily percieve a need that wasn't really there, and dedicate considerable effort to fulfilling that need, only to find that nobody actually has such a need. Again, look at a lot of the crazy patents out there.

Or perhaps those with less int just cannot fathom the point of such items.

Wizard: "What do you mean a spoon that creates non-sustaining gruel is useless? I love the taste of gruel!"

Or maybe some wizards are just crazy.

As to the stupidly powerful weapons and armour, I always considered them not made but empowered. Your average 15+ level adventurer is always off battling reality shattering enemies, fighting the gods themselves, hanging out on other planes of existence and all manner of other weird environments. Since weapons last longer than people (Usually) after a while they've absorbed so much "magical radiation" that they've got all kinds of crazy powers. It might start out as a +3 or +4, then grow in power as it passes through more hands and does the same things.

Now that's a pretty neat idea.