While I don't agree with the assertion that "Samsung are bastards," they very obviously used a PDMI connector because it looked more like Apple's dock connector at the time.
Not only did they not use micro-USB like most manufacturers, I recall reading that their PDMI implementation was non-standard (i.e., not-quite-PDMI). There was no reason for them to choose such an incompatible connector other than the shape resembled an Apple connector.
