I always assumed it was that plus sort of a weed-out thing, as well.
That was my assumption as well. I generally feel like a bit of an asshat skiing with a beacon but without a shovel, probe, and first-aid kit ("I want you to dig my ass out if something unexpected happens, but I don't want to bother being prepared to help others"), but I have done it inbounds on days that seemed relatively low-risk. Or, to put it in Bridger terms, so little fresh snow that there was no line at Schlassman's. Hiking the ridge, I'd generally have my full kit with me, if for no other reason than wanting to throw my skis on my pack for the hike up. I do find the contrast with Big Sky's policy (beacon, shovel, probe & partner required) for their beacon-required terrain.
For those who haven't had the opportunity to ski the Ridge or Schlasman's, it's almost entirely unmarked terrain, with enough cliff bands and other obstacles to put a premium on knowing where you're going. There are also enough skiers at BB who
like to drop cliffs that blindly following tracks is ill-advised. Without the beacon requirement, I"m sure there would be more unwitting skiers and riders getting themselves into bad spots and needing assistance.
I own a BCA Tracker 3 and a Pieps DSP Pro. I bought the latter so that I could make the former my loan-to-a-friend beacon, and it has now become my fiance's beacon. It's small and, IMO, nearly idiot-proof to use, which make it a pretty good "maybe I should just be wearing one" beacon. If you have an appropriate pants pocket with a retaining clip, it's damned easy to wear that way; it's also small enough not to be particularly bulky when worn on a harness.
At the end of the day, my two cents is that wearing the beacon in-bounds mitigates a low-likelihood, high-impact risk with minimal cost to you (if anything, it makes it more likely that you'll actually use the batteries before needing to swap them on age). If you're comfortable wearing a pack, or if you want one anyhow for a layer, a snack, and some water, then adding in a shovel, probe, and first-aid kit again has minimal impact on you, while mitigating a high-impact risk. It also helps avoid the human-factors trap of "oh, well, I didn't carry it because I was planning on staying in-bounds, but then I ran into Joe, and he's got this cool idea about that line just outside the gates."
Re: the notion that we may see in-bounds avalanches as skiers and snowboarders push areas to open more inherently risky terrain, there's probably some statistical truth to that (more exposure = more incidents, even if the risk stays the same), but I think it's probably worth considering in perspective, too: that Taos avalanche made national news precisely because of how rare it was. That doesn't help those directly affected, but it's important to consider when deciding what risk-mitigation activities are necessary for the future.
