How many pouches do these wizards have anyway? What happens if they pull out their tiny mirror to find it smeared in bat guano? Trying to find the little iron bar, but get the little glass one by mistake.
Its just always seemed rather hokey. I have been tempted just to get rid of all the minor components, unless they are particualy important or receive the effect like good berrys. But for means of not complecating the game I haven't.
For those that prefer their mages to be breaking cricket legs and hurling dung at their foes, eskew matterials is useful for combineing with metamagics when your trapped/bound or need to be discrete in some way. Eg the mage tied to the chair, can't reach his pouch, can't flap his hands around, no problem, say "micky mouse" and your free. (er...presumeing you planned your spell selection very well)