I suspect that(aside from sheer shoddiness and not caring) the ‘counterfeit’ as opposed to ‘3rd party’ aspect of things is a serious problem here.
Sure, for a basic sub-100w line-lump AC adapter, you aren’t fighting for every millimeter of space; but if you want to produce a visually identical clone of one of Apple’s fetishistically compact adapters, yes you are; and you are almost certainly trying to do so with a lower bill of materials and quite possibly less competent engineers.
You would certainly still see other flavors of corner cutting, in the name of price; but if the product were a generic black box type adapter with a magsafe connector, it would be much more likely that they’d spare the few extra millimeters of FR4 required to produce a vaguely reasonable design.
