US Elektra 7" white label promo vs. unique release

Hey folks,

usually a promo single for radio stations or similar things should be more limited then unique single releases. So how is it possible that on Ebay unique singles of "Keep Yourself Alive" or "Liar" sale for higher prices then the whities?
Also I think the white label 7"s appear much more often then they actually should. Are there fakes circulating?

kind regards,
W.

Simple. The regular releases didnt sell, while every radio station got a white label promo.

Result: more white labels are in circulation. Hence the price.

Jap, that sounds logical. Thank you!