If I think that a certain item will have a use down the road, it goes into my inventory. However low level weapons (like Pistols, knives etc) and clothing I leave alone. I keep any and all explosives and medical supplies I can get my mitts on, same goes for ammunition and I keep a spare set of weapons just in case. Teleporters are a little too random for me, so I ignore them and I use my characters starting clothing as a way to distinguish the roles I have available to me.
As for equipping armour, I know its a free action when the map is clear, but I tend to only equip armour when I need it, which tends to be when I'm room breaching, which has the potential for close ranged interrupts. Its a case of knowing that I'm going to take damage and taking steps to mitigate the amount of damage I take. I don't have armour equipped all the time because the time I would lose due to encumbrance isn't worth the few points of DR that the armour gives.
Also, regarding the title, it was a minor observation, that's all. Hell, I've made one myself.