I think you're confusing things here.
DX don't meter their lasers not because they can't (like idiot said, they can buy their own no sweat) but because they don't care.
They just sell what they're given. If it's crap, they'll just wait for you to respond. Most people don't have power meters and can't figure out if it's underpowered, and lots more wouldn't of seen a high powered laser before and wouldn't even know if it was underpowered or not. Most people wouldn't even know what they got is crap.
If DX had to send back every second laser they got for being underpowered, they'd lose a lot of money, even if they did gain a lot of respect from us. Business economics.
EDIT: Crossposted by Razako.