In the Scanlists column, just double-click and you'll be presented with a box where you can select any or all (or even none!) scanlists you'd like to put that object into.
So really, you are not moving / copying frequencies, you are just using the Scanlist column to grant or revoke *membership* in a scanlist. This is a major timesaver compared to the old way of being frequency-centric, rather than scanlist-membership centric. Hope I said that right.
If it helps, you can double-click on the Scanlist tab itself, and the scanlist memberships will be shown from lowest-to-highest, or visca-versca.
Of course, I'm only talking about conventional system programming, and not trunking.