I do agree with Swift's point in that for the most part; most people I know that collect CE guides (which isn't that many to begin with) keep them sealed. It's because most of us, like me, only buy the guide to collect; and not actually use.
The last guide I actually opened was probably Bioshock Infinite, but like Coma said, it was for the toy
Now, I don't go out of my way (well that's a lie because I just drove 13 miles today to get the Injustice CE guide at 50% off) usually to buy them. I also try to not overpay - or even pay full price.
Most CE guides go on sale, even the "rare" ones before they sell out.
For example, before the 1st run of Skyrim guides became overpriced on ebay; they were cheaper than the MSRP on amazon lol.
The only guide I'm considering paying full MSRP right now is the MGR Revengence CE guide...just because online is overpriced, and Best Buy apparently "took it out of their system" completely.