Two obvious issues here:
1) The feed is old, and nutritional value has started to decline. You said you have 3 bags? Are they all that old? I know this is tough to hear (especially with prices right now) but you may be best served with tossing those and getting a new bag with a more recent mill date.
2) They've become spoiled and used to eating all the yummy extras you treat them with, so they're rather hold out and get treats instead of eating feed.
In addition, S&P or any other whole grain mash feed is best fed fermented or at least wet. S&P even recommends it on their site: https://www.scratchandpeck.com/wp-content/uploads/Scratch-and-Peck-Feeds-How-to-Ferment-Feeds.pdf By serving it dry, the chickens aren't eating all the protein, vitamins and minerals that are added to make this a nutritionally complete feed - so they're not getting the nutrition they need and are also wasting a good 5-10% of the feed that way.
1) The feed is old, and nutritional value has started to decline. You said you have 3 bags? Are they all that old? I know this is tough to hear (especially with prices right now) but you may be best served with tossing those and getting a new bag with a more recent mill date.
2) They've become spoiled and used to eating all the yummy extras you treat them with, so they're rather hold out and get treats instead of eating feed.
In addition, S&P or any other whole grain mash feed is best fed fermented or at least wet. S&P even recommends it on their site: https://www.scratchandpeck.com/wp-content/uploads/Scratch-and-Peck-Feeds-How-to-Ferment-Feeds.pdf By serving it dry, the chickens aren't eating all the protein, vitamins and minerals that are added to make this a nutritionally complete feed - so they're not getting the nutrition they need and are also wasting a good 5-10% of the feed that way.