The big processed food brands are clearly more aggressive in their discounts. Lower demand overall from GLP1s or common sense is part of it. But the other factor relates to the huge increases in prices starting during the pandemic.
I mean, 13 ounce bag of Doritos for $7.29? A box of freaking Cheerios for $5.99? Few people will touch that, so they're in a situation where they must discount heavily to move product. These particular products are on sale 2-3 weeks every month at $2.29 to $2.99 (see https://www.starmarket.com/weeklyad)