Purchasing a coveted clothing item you had your eyes on for a long time is incredibly rewarding, especially if you earn the tokens manually (ie, not getting them from RR+).
When you're in your dorm, and you buy a clothing item off the watch store (or the mirror), perhaps you could hear a knock at your door and then the box will spawn a few feet from it like a box normally would. If the box cannot spawn at the door (such as if the player blocked off the door), it'll spawn at the player like it normally does.
Upon buying an item from a watch menu, it should then show a page saying "Purchase Complete!", with some subtext saying "Your order will be here soon shortly..."
As for why, it would make earning cosmetics with tokens much more satisfying. Player satisfaction is a very strong element; and can keep players coming back for more.
With the current setup, if you buy a cosmetic off the watch shop, it'll pop a box in front of you and that's it. With the mirror, you don't even get that; no box, no sound, nothing.
Compare this to buying cosmetics at a shop counter, where you get a nice sound and visual effect. It feels much more like you're EARNING that clothing item, increasing player engagement.
The texture for a package bought using the watch or via the mirror should be of a typical cardboard box, with a black rec room logo on the sides; kinda like an Amazon box.
If not for player satisfaction, it is still a nice touch.