On bookstores...

I love my local bookstores and the people that work there.  I do wonder sometimes how they come up with where to put what.

I wanted to re-read the Fever series by Karen Marie Moning (a fantastic series btw) which I had originally purchased in ebook form but I couldn't find it.  I couldn't figure out which online retailer I had purchased it from and with my luck they were probably drm'd for my palm pilot.  I decided to re-purchase the series in paper as I am sure I will read and re-read this series again and again.  There are five books in this series.  I found two in Romance, two in Fiction and one in SF/Fantasy.  How does this happen?  I am currently reading The Curse (Belador #3) by Sherrilyn Kenyon & Dianna Love.  These books are Urban Fantasy but I found them in Romance.  I'm pretty sure that guys would love these books but they aren't even going to give them a try if they are filed under Romance.  Can anyone explain the thinking behind this to me?