Pretty much every data connector has its pins exposed to the air and subsequently ingress of dust and liquid when not mated. Having a big metal enclosures/ground planes/shields around the connector is about electrical noise control and sometimes to a limited degree about preventing mechanical damage.
The old apple connector was awful, prone to breakages and pin-lifting due to "real humans" using the devices, it also was a significant pain to replace in the iPod Touch due to its wide body and numerous pins ( at least the phones had a replacable flex lead containing the dock connector ), it was also exceptionally good at picking up crap (lint, paper, body gunk, drinks
The MicroUSB connector on phones usually are mashed due to people deciding "No, it really MUST fit this way". The SONY Xperia with the Micro-A was a wonderful disaster in that respect ( yes, I know the key is offset to prevent incorrect insertion, but it's useless against determined humans ), or due to looser tolerances the tongue gets partially sheared away when the phone is dropped on the connector while plugged in.
Who knows how people manage to break things in strange ways, but they do, "we" might not, but "they" certainly do.