I'm not on the spectrum but i do have ADHD and did the exact same shit. Would walk off in the store. Would walk off at the amusement park. Would walk off wherever the fuck just because. Hell, I still do it, but I'm an adult now so nobody can tell me not too. Tbh this is why I'm not necessarily against "leashing" assuming it's one of those backpacks or something, even though it does look odd