People use elves, dwarves, orcs, and goblins because people KNOW those things. A lot of the times when authors try to do something different it just gets conceptualized as 'Oh, that's just an elf with cloven feet' or something similiar.
People have their symbols, writers use them, and move on to important things like figuring out what to do with them. Dragon Age differentiates itself not because it has the same dwarves and elves, but because those dwarves and elves are different than people know them. They take the symbols and turn them on your end.
The real question needs to be asked.. what is to be gained by using different races? If the answer is 'you can use different races' without any internal substance... then you're not really doing a service.