Chinese Chewing Gum

Recently I stopped in Shuǐlǐ 水里 while on my way to Pǔlǐ 埔里 by scooter. There, while waiting out a rainstorm on the main street in front of the historic train station, I noticed an unusual betel nut booth with a fetching green sign. “Chinese chewing gum” is a curious phrase, not one I recall noticing before, and it is also peculiar to see an exclusively English sign out here in the mountainous heart of the nation. Searching around, I chanced upon a short documentary describing betel nut as Taiwan chewing gum, which still sounds somewhat odd. What sort of gum gets you high and stains your teeth red?