> I think that the very idea behind IP laws in the first place was to protect effort

No, this is know as a "sweat of the brow" interpretation and has been rejected by the US Supreme Court. http://en.wikipedia.org/wiki/Sweat_of_the_brow

Just because something takes effort does not mean it should be protected. Just because a person could make more money by having exclusivity does not mean that thing should be protected.

I haven't thought about the issue of magic tricks enough to know what I think about it, but I definitely resist the notion that something should be protected simply because it took work to create. That way leads to a society where everything is pay-per-view. For example, just because I scan an old book doesn't mean I should own a copyright on the scan.