Distribution of resources is not as efficient as you might think it is.
Faster-than-light travel does not eliminate travel time altogether, so there is still a need to distribute resources to the planets that need - or rather, the planets that can pay - for it. Most of that will probably be planets like Coursicant and other trading hubs, while edge worlds like Tattooine, where moisture is a rarity, will get shafted.
Meanwhile, planets like Couriscant have the same problem that all big cities have - resources are directed largely towards the top of society, while the bottom has to scrape by with what they can get, and often it's not nearly enough.
But all of that is gravy, because the truth is that Star Wars isn't a pre-scarcity universe. They just have more grand and elaborate societies than we do. Massive city planets, cloud-based mining facilities, beautiful planets of paradise, none of which eliminate the need to produce resources like food, water, and shelter for all of the thousands and thousands of planets in the galaxy.
Just because they're bigger and more advanced in some ways (ever notice how there's no paper in Star Wars?) doesn't mean their resources are infinite or post-scarcity.