Op, you asked why. Many of is with ADHD need constant motion to be settled and focused. It sounds counter-intuitive, this is how our brain works - our brains are wired atypically. I chew gum a lot. Due to the choking hazard a PP mentioned, I would spit it out for yoga, particularly if asked.

I stopped chewing gum when I realized that I didn’t realize when I was popping it. I wouldn’t be offended as long as the person bringing it to my attention was polite about it.