In this case, it's the pre-order bonus items that're driving the gouger greed. The only way to avoid it is to have just a single release type, where all copies (even if reprinted) are identical in every way.
Even then and no matter how many copies are made, someone will try to gouge for silly prices. Look at the morons buying overpriced Dracula X booties, even though they can still be bought brand new from Tobias for less.