I think that's why they get a lot of criticism from traditionalists. (Not saying you're one. Just springing off your observation to address the issue more fully.) They're using a different paradigm, and that's terribly disorienting to someone who confuses the method with the message. How many "mainline" churches in America have fought to preserve the method for a hundred years while loosing the message (and attendance as well)?
Actually, to contradict myself somewhat, the idea of a "seeker service" -- a service that's oriented towards non-believing seekers, not Christians -- is quite old. I believe they had them in Presbyterian churches a hundred years ago. Probably more hellfire preaching that we'd use today, but the method is not more sacred than the message.
I do consider myself a traditionalist. I see nothing wrong in that. My experience with the seeker type services of Willow Creek and other denomonations that use the model has been disappointing. The denomination I used to belong to, the CRC, had a couple mega churches that I went to from time to time. One church in particular each time I went, and it was Sunday morning, I did not hear a sermon. Because the church was so large the pastor held a information service to explain a change in a few programs.
I have a couple of friends who attend Willow Creek on a fairly regular basis, they are not members but like the church because they don't feel threatened there. In my opinion you should feel threatened in church. You should be challanged, but since they don't get that they like it.
Now Willow Creek may have changed some thoughts on this, but the last I knew there was no real push to contribute to the church. If you want to join, great, but there is no push to do anything but be entertianed. It makes more sense to me to have some obligation from the church on the members to contribute to the church, and I don't mean finacially. But in programs and displine.