More to the point I believe, is running an expensive loco outdoors, many of the high end electrics are kept on shelves or in the box.
good on you running it and enjoying those nicely detailed locos, with all the extras of great smoke, sound, and things like animation.
I also agree that when you get a number of locos, battery power is way too expensive. I still have 40 decoders to install, and thinking of doubling the electronics cost to go battery would make for fewer locos in the collection.
More and more locos are being made with a socket that could make DCC/Sound optional, but the DCC decoders are so cheap now as part of the loco cost it's not an option that is often offered. I suspect this is more to do with selling the loco and decoder combination for more profit as opposed to selling the loco DC only.
You see this in HO also, the largest market.
Greg