Most auto manufacturers have an employee discount system of some sort. In that case, it's pretty likely that it would apply to any M-B product. At least here in North America, it still has to go through a dealer.
On Corvettes, the shipping charges are the same no matter if you are in California or Kentucky where they are built. In fact, if you opt for museum delivery, you still pay shipping charges and the museum delivery fee.
Mercedes has a program where employees can purchase a Mercedes at a great discount.
Most then resell them to the general public. VW had this too and probably still have it.
I don't know how smart fits into this?