Hopefully people paying for hotspot would be the last to be throttled, unless their usage was absolutely absurd (like 24/7 torrenting or something).
Now that's funny right there! While they could throttle on a person-by-person basis and they could give preference to the hotspot users don't hold your breath. What good would it be to throttle that average user that's NOT downloading the 1GB torrent from a hotspot -- not much bandwidth to be gained. However, if you throttle the hotspot user that is downloading that 1GB torrent there is some bandwidth to be free'd up.
The model for this is satellite internet and there "fair use" provisions. You get decent download speed for a bit then they throttle you back to a crawl. When the pipe is of limited size what do you expect?
I expect the throttle plan will be driven by demand and when demand is high they will lower the setting. I'd guess that 1 hotspot user will eat, when they're using it, at least 10X the bandwidth of a non hotspot user so the more people using the hotspot feature, whether it be legaly or not, the more the throttle will be lowered.
Brian