Please don't tell me "what not to bring up", Nate. This is an open board and I'll bring up anything which I think contributes to the discussion.
Copyright law is highly relevent to a discussion of what one can or cannot do with an eBook, and applies equally to electronic media as to "physical" ones. One is certainly not buying the "content" of an eBook in the sense of buying any "rights" to it. Given the definition of the word "licence" as "formal permission from a governmental or other constituted authority to do something", then it is copyright law which forms the basis of the rights that the author or publisher is licensing you when you purchase an eBook. You cannot talk about "licensing" without talking about copyright law.
DRM determines whether or not one can re-sell an eBook, and that is determined by whether or not the publisher makes provision for the DRM to be transferred to a new owner. I don't believe that there is any legal requirement for them to do so, and it could well be argued that it's not in either a publisher or an author's interest to do so.
However, given that DRM-ed eBooks have no resale value as a result, from the viewpoint of the customer one could argue to a publisher than this lowers their value, so the price should be correspondingly lower as a result.