really $5 is all that is holding you back? Odd reasoning... if you want to play I wouldn't imagine $5 being the deciding factor.
$15 versus $10 is a huge difference in terms of impulse buys. $15 is an exorbitant rate and was exorbitant at the time of release (50% higher than Everquest), let alone 10 years later. The reality is I don't play WoW much even when I am subscribed, but if I'm paying that much and not using it, I feel like I'm being robbed. They have to lower the sub price -- I guarantee that is what keeps many lapsed players away.