Is this even enforceable? Once you've purchased something you can give it away with whatever offer you want. Can someone with a legal background comment on whether apple has any legs to stand on with this argument or if it's just blowing smoke?
I suspect that like basseq says, the real target are those annoying web ads that promise free iPads if you click on them.
An example, one option that came up when we were discussing gifts for our non-profit's upcoming conference was to give away iPads.
If we did go with the iPads as gifts, we would just be giving them as gifts for the winners of research competitions (ie a gift-wrapped package), not as a way to promote the organization. In that circumstance, there probably wouldn't be any problem giving the iPads to the people and no legal issue would arise.
However if we were using the Free iPad offer as a way to promote the organization (ie in advertising, a banner or in our printed promotional material), we might get a cease-and-desist letter asking us to not use their trademark. And they might have a leg to stand on there.
edit: added some clarifying details