I think Amazon is way more an adult thing. You know, kids just buy it on iTunes or on the store. But I could be wrong. Anyway it looks like Pentatonix have are doing better on physical department.
Demi's physical albums are literally everywhere. She's got her official page selling the bundles, the page selling the signed copies, and many others, so this doesn't mean much.
I think Amazon is way more an adult thing. You know, kids just buy it on iTunes or on the store. But I could be wrong. Anyway it looks like Pentatonix have are doing better on physical department.
If Demi and Pentatonix are set to have almost the same sales, Demi will get #1 because of streams and the singles success, i dont think we should worry that much. Just stream the songs on Spotify and the videos on Youtube.