For those of us with disabilities, it's nice to walk in an urban area and be able to scope out a micro. I find them a lot more challenging than to traipse through the woods to find the standard ammo can filled with golf balls, McDonald Happy Meal Toys and hotel shampoo bottles.
I'm not saying that one is better than the other, but I think both are equally valuable to different people.
Quite honestly, if I had my choice of seeking a micro or seeking an ammo can, I'd just as soon challenge myself with the micro. Besides, the kids always fight over who gets to trade swag in the large cache, and with a micro, we don't have that problem.
Don't ban them. Just hate them secretly. Just my .02