While I'm sure every affiliate would prefer a lifetime revshare, this method does put the customers back out for others to earn money off of. It helps reduce saturation that you'll find with promoting other big sites.
Of course, a significant % of customers will not come back through another webmaster's link, some do (intentionally or not) and it's easy money for the secondary webmaster. And you figure, if a big fish kind of guy is on the site buying for months/years, a few times at least he'll get cookied again. So what you lose in referring new customers you can make back a healthy amount in these cases.
Bottom line: There's a reason why so many still promote them despite the cookie issue. The money is still there to be made.
And yes, I'm flying their link in my sig so my vote/opinion may not count. That's up to you.
