Potentially as a side effect. A lot of ingredients are switched to cheaper, often more processed substitutes.
For example, vegtable oil instead of olive oil, fructose corn syrup instead of honey or sugar.
Beyond that chainging composition to reduce amount of expensive ingredients. Think Pesto Genovese which is originally Parmesan, Basil, pine nuts, etc. Instead of only pine nuts, you now include other nuts for texture and only add a smaller amount for flavour (and worse add flavoring so customers don't notice too quickly).