On the other hand, Vertigo does the exact opposite and prices all of it's first issues at $1, probably hooking more readers than they would have done at a normal price. It's a smart and time-old strategy used by drug dealers: the first hit is cheap, but the ones after it aren't. Image, Marvel and DC have begun toying with the idea, although not with first issues of new series, but rather with old #1 issues of old series. Such promotions are almost guaranteed loses for the company, but books like The Unwritten have gotten a higher profile because of it ("You have to lose money to make money" is an very common business motto).
Perhaps having a larger company behind their financing allows DC to absorb more loses when it comes to series. And certain books in Marvel have gotten equal time, such as Nextwave, The Order and Agents of Atlas before getting canceled. I think that is a fair number of issues for any series to have to try attain a readership, and perhaps with the new Disney deal in place, Marvel will also allow more series to last a bit longer.