This is actually our favorite little secret! We have stayed in the Toy Story Building all 3 trips to ASMo and figured out early on that it is MUCH easier and faster to take the Music bus back at park closing.
If you look at the map you will see that Toy Story is all the way to the far side of Movies, but it is still not a bad walk from the Music Bus Stop, just across a lot and through the Movies resort. It really looks much further than on the map. And when you consider the difference is between standing ON YOUR FEET waiting for the Movies Bus for sometimes over an hour (or close to 2 if it is MK on a Spectro night!) or waiting 30 mins or less for a Music bus, getting on and walking just a few minutes to your room it is COMPLETELY worth it. We were in the room, jammies on, teeth brushed, and on our way to dreamland before we probably would have even been on a bus back to Movies on some of the busier nights (and we only go in Value/Off season times).
The walk back to the room is probably shorter than the walk was from the Castle to the bus stop.
And we weren't the only ones! In fact most of the people on the bus with us got off and started across the lot! No matter where you are in Movies, it is absolutely worth it if the wait is shorter at Music. Haven't tried it at Sports, but I would think during really busy times it would also be shorter. Remember, you will be standing waiting for the bus, so it is really no different than adding an extra 30 mins to your Park touring day. Would you have continued Touring for an extra 30 mins if the park had stayed open????