Those screenshots are hilarious. I, too, often am amazed what people do to make their game as hard as possible.
But... We have to remember that some people bring back characters from the good old times, when equipping a mage with physical damage gear actually made sense. Especially necro damage was so low that many saw it as an improvement to equip +combat rating and +dex and use a crossbow.
You can still see traces of this in the current game: There's a permanent debuff for Weapon Damage (ranged) on mages - if I remember correctly, that was introduced to stop that crazyness from happening.
So, if you see a necromancer in old school equipment and crossbow equipment, he or she may actually have been a top player seven years ago, although it looks noobish today.
Weird, eh?