Mobile bandwidth still occurs with offline playlists

[venom400]

Plan

Premium w/ Hulu

Country

 USA

Device

LG Zone 3, Linux Desktop

Operating System

Android, Debian

My Question or Issue

OK this is extremely annoying:

I recently purchased a bluetooth speaker, and I was really enjoying the convienence of being able to control music playback and volume control from the phones lock screen, awesome. BUT WAIT!

Online gaming is IMPOSSIBLE!

Ok, so I'm streaming music and that  causes lag, stupid me right? Wrong.
I'm playing an offline playlist. In fact, all my saved music is saved for offline.

I troubleshooted this by trying the speaker with my desktop like I used to do with my old bluetooth speaker set up. No problems whatsoever, so Spotify expects me to always play my music via Spotify connect to my desktop from my phone? No way, I'm not doing anything as inconvienent as that with a service that I pay money for.

So here's the deal, why on earth, can't I skip the middle man, and just connect to my speaker from my phone and play my music without having my games ruined?
I've read that the mobile app uses P2P, ok, whatever, but if I went through the trouble to download ALL my content, I shouldn't have to worry about the app wrecking my bandwidth without my permission, especially when I've taken measures to prevent such a thing by downloading my content.
Fix this, someone.