Stephanie isn't portrayed as a bad crime-fighter because she's poor. She's portrayed as a "lesser" crime-fighter because she's young and (especially compared to the rest of the batclan) barely trained (and every time someone writes her getting training . . . the next guy forgets it). She's moderately well-adjusted, she's enthusiastic, she wants to do good. If she were in Metropolis, Superman would probably try to stop her because she has no super powers . . . and because she's young. Not because of her economic status.
Again, you kind of have to want it to be there, and warp the characters to get it.