This just triggered a memory synapse that probably has been unused for literal decades about how when I was a kid we only could buy really bad chewing gum in our village, the type that quickly lost flavor and ended up really tough to chew, and how we would experiment with eating something else like licorice or a cookie to re-introduce flavor or soften it up. Even thinking about the texture of chewing gum mixed with brittle cookies now grosses me out, but childhood me had different tastes I guess.
It has to do with saliva enzymes, i'm told.