What´s the reasoning for carry and equip items in Munchkin?
You equip items so you can get their benefits.

But there are restrictions to what you can equip. You can't equip items for which you don't have the required free body slots (e.g. hand). You can't equip items for which you don't meet race and class requirements. You can't equip "use only once" items.

You keep items you can't equip in your hand to protect them from traps and thieves, and to hide what they are from other players.

But there are limits to one's hand size.

You carry items you can't equip and won't fit in your hand to avoid having to discard them, or worse, having to give them to another player through the charity rule.



Note that you might hold back from equipping an item in your hand if you think you might lose it (e.g. to a thief, especially one at level 1), but there's virtually no reason not to equip something you can equip if you're currently carrying it.