Until quite recently most promotional pricing did not apply to stores.
I'm of the opinion that this was because:
Store owners are already getting price breaks over other sellers, as well as some perks (the ability to use Vacation setting, for example)
The promotions were meant to attract new sellers or occasional sellers to the site, increasing the number of listings, often just in time for a quarterly report.
They were not designed as a reward for current sellers, who eBay thinks are here to stay. 
When you see any offer, it's worth deciding if it is really any use. For example, I get lots of dishwasher detergent coupons in the mail, but the couponed products are still more expensive than the detergent I normally use.
In the same way, a Free listing that doesn't sell, costs you your time -- at 17 cents a minute, and if you use Good Til Cancelled, next month it will cost you whatever your normal rate is.