OK. When in doubt, read the regulations. After doing that, they're not tremendously obvious: The "can't use a bear box" regulation applies only to the three areas in Sequoia Kings where hanging is prohibited (Dusy Basin, Mather/Rae/Kearsarge/Bubbs/Forester & Rock Creek). And what the reg says is you must have enough canisters to carry all your food & garbage.
Makes sense, if your required to have a barrel then you shouldn't need the box and it can be saved for those who need it.
I find it interesting that thru hikers aren't required to have a barrel, the ranger that was giving me an ear full was going on about if you can't make it then you will not have one which is perfectly sound logic, same applies when I told her I did not have a wag bag and she got upset again

I knew I would be ok and wouldn't need it but she used the same idea that "you never know" and made me take hers, I still have it here at home.

I dunno if I'm following you here. Again, it's not the bears "playing" with anything that's the problem, it's that their natural behavior is changed by us not securing our food in a bomb-proof way. The Ursacks have been shown to not be bomb proof. Bears get a "food reward" -- either a tiny taste or enough positive reinforcement to keep trying to get into the sack. So you can use it but, as noted, only to counter balance like a regular stuff sack -- not leave out on the ground because, like a stuff sack, it doesn't work... .
Ok I was more under the impression that the Ursack was bomb proof and it's only down fall was that the bears can carry it away.
Well, kinda, sorta... . The objection to the boxes is that they're an aesthetic intrusion in a Wilderness setting
Lol I think people get worked up over such insignificant things, I have never looked at a bear box and thought it's ugly or distracting from the wilderness around me, it's like while doing trail maintenance we try to get the cut brush out of sight but I have never walked along on a trail and thought a pile of dead brush was distracting, I mean there is dead fall all over the place, it's a part of the forest!
We can quibble forever in a scholarly debate on what is and is not allowed and where. But again! It's all about keeping food away from bears.
Lol I don't want to quibble I want to learn, I like to know exactly what the law is in all things in life, but I admit the rest is an endless debate on what methods should and shouldn't be used.