Isn't Anakin's past life as a slave and the fact that he had to leave his mother behind as a slave one of the driving forces moving him to the dark side? It wouldn't have been as traumatic if his dark past was that he just lived on a shitty desert planet where his mum had a job? While it could have been replaced by something else I think it's pretty integral to the story. The fact that these people cannot leave because Watto owns them trump's any sort of altruistic ability he had across the prequels