If you have a beacon, there is no reason not to use it on any day where avalanche risk and treewells are a factor. I certainly don't wear mine every day.
As for how many people are skiing with a beacon, you may be surprised. On a good number of powder days around here, I've clicked mine over top search in lift lines of maybe 40 people, and had my beacon report 4+ signals (the most my beacon can report), with no patrollers visible in range. That means at least 1 in 10 are wearing a beacon and possibly more.
Even if you are wearing a beacon and none of your friends are (assuming you ski avalanche/tree well terrain with friends, which is probably more important than wearing a beacon), patrol is going to have a beacon and has at least a sporting change of locating you and getting you out in the 15 minute window. If they have to get on site and then set up a probe line, things are a lot more dire.
As for whether this is an academic concern, this is earlier this year.
Full disclosure, I had my beacon in my pack and off when this slide happened. I packed it that day and then never bothered to bring it out. Dumb.
That is the 3rd inbounds avalanche I have kicked off in the past decade, and it was by far the smallest. Probably not enough to bury me, but it had a good chance of bouncing me off a tree or wrenching me up pretty good. The other two were more than enough to bury me. One fractured right at my skis and I fell uphill against the crown, the other I was right at the edge of the slab when it broke and it again didn't get me. The largest had a 40' crown about 2-3 feet deep and ran into tight trees.