[TimT]

Chances are he does not have a K&N filter in the car, slim to none chance but..

The overabundance of K&N stickers might be for contingencies...

Sponsors points etc..

Like Tire Rack required windshield banners in on the cars in BMWCCA racing a few years ago..

And they gave away tires to winning cars...

Sport a Grassroots sticker on your car.... you may get a pic in the magazine...

K&N might have some sort of sponsorship with whatever group the car is involved with...