Try a freshly made juice, either your own diy or from a local store and tell me, that there was no difference to the juices you buy online , which are pre steeped by either the company or reseller.
Some juices that fall in the desert isle are better or you're getting full flavor note/profile after steeping.
If you keep your liquid in the kitchen cupboard, out of reach from your kids, and it has closed doors, surprise you're indirectly steeping.
Steeping doesn't have to be in a box, closet, crock pot, closet or even a ultrasonic cleanser. Taking it out of direct light sources including sun light and placing it, in a dark place, is the process of steeping. You might not leave it there for some weeks, as many of us do, but if it stands there a week, even if used during that time, its the same. Again it was pre steeped by the vendor you got it from anyways and in most cases that's enough to enjoy most flavors right out the mailbox or store front.
If you're using a RDTA for example, you'll notice the difference, not so much with sub ohm tanks.