[loramin]

What Jimjam said, but also inventory slots can hold clickable items. For instance, every non-Bard will want boots that increase run speed (Journeyman's Boots for most; Shaman get a faster version).

You can wear the boots, but most right-click them from inventory instead, because they have bad stats. Other inventory-clickable items include potions, root nets, or a Mage focus item (only Mages can equip them, but other pet classes can still use them from inventory).

On my characters I tend to use six bags, or rarely seven. I always leave a slot for my SoW potion or run speed boots, and typically I have a second clicky in another slot. With ten-slot bags that still lets me hold sixty items, which is usually plenty.