It's just an idea ripped off from one writer.... that other fantasy writers seemingly can't escape.
http://tvtropes.org/...esAreAllTheSame
What annoys me though is that dwarf fans aren't happy with already borrowing some human ideas (like Scots). They now have to rip off other typical human behavior in DAI. Nothing's ever good enough. Dwarf fans just want to be human.. but have a desire to look like ****. For some reason.
While Dwarves may often be cast in typical roles, this need not restrict Players from loosening said roles. I have been playing Dwarven characters since '75 in D&D settings, the first of which married an Aerial amazon. In NWN1, in a five yr on-line campaign, my Dwarven Rogue was partially possessed by an Elven spirit. From there, Clan McJagger became widely known as merchant archers. Their personalities are somewhat between that of that of Hamish and Ferengi, but prefer to wield longbows. And in the DA series, my Dwarves have also become archers of the first order, though still preferring heavy armor if possible. Etc.
Height, appearance, etc simply does not need to dictate what one may do with a given race for purposes of RP, Dwarves included.