My Delightful Dozen don't go through much food at all. They get 3 - 4 hours of free range in the evenings. I purchased a 50 lb bag and it has lasted me more than a month. I don't think I will need any more until I am ready to put them on layer feed in late August.
Once I put the feeder up on a brick they no longer go through the feed so quickly and wastefully. They get daily snacks of things like corn on the cob, zucchini, broccoli, nearly gone fruit, but primarily they are eating the feed provided. This afternoon, I commented to DH how shiny the feathers are in the sunlight!
I really do think that feeder placement is what has make my DDozen less wasteful.
Edited to add, they are 3 months old now, we got them in April.