Could use a reference. The wear will depend a lot on your area - mountain roads will kill it faster than suburban commute. But either way, I tried to find anything more authoritative than a forum post (which say anything between 100k and 300k), and it's pretty hard to do. Have you got a link with an actual survey or producer stats?
It helps that I actually know how to drive and not burn the fuck out of a clutch too I'd imagine. You see very dumb people in my country using their clutch to hold their car stationary on a hill, what the hell that is all about I'll never know.
But overall, there are hydraulic losses in classic planetary automatic gearboxes, and they are also heavier.
For instance,
http://www.consumerreports.org/cro/2012/01/save-gas-and-mone...
Personal experience: I regretted buying a Renault Laguna with automatic box. Horrible fuel economy. Even the torque lock didn't help, also highway economy was quite bad which was very surprising. Other than that, a nice car.
And before someone mentions it, a clutch wearing out during the working life of a modern manual car is a joke. I've driven multiple manual cars to over 200k miles and never had to replace a clutch. If you wear out a clutch your car is defected or (more likely) you're utterly terrible at driving stick