I always thought MBZ (post '70s anyway) was a well-regarded slushbox manufacturer? My brother's '80 Porsche 928S has an MBZ auto, as I recall.
As to the Mercedes philosophy, having been to Germany a couple of times now I feel confident that the manufacturer prefers you drive a manual transmission car, for the increased control it gives you as an operator. The Germans take their driving VERY seriously, and having a stick affords quite a bit more control in the hands of a qualified driver.
Maybe because we have so few of those here in the US, we prefer the automatics we buy. I know I wish there were a reasonable way to stuff a 5 or 6 speed in my 500