Anytime I see people defend this kind of practice, the John Ruskin quote comes to mind: “The dullest of all excuses for usury is that some kind of good is done by the usurer.”
Many people make use of payday loans. If you remove that option, those people aren't any better off. Restricting or prohibiting payday loans is politicians saying they can make better choices than the people they're claiming to help. Does it come from good intentions? Of course. But it's also fundamentally elitist.
Only that they are heavily regulated to ensure that (a) consumers are fully informed, (b) no lending occurs to people who can't afford them and (c) interest rates are capped to reasonably levels.