You could just slide right through, but as others said you take the chance of getting charged out the wazoo. I always declare what I have and then go into the "To Declare" line (it's never got people in line anyway so it's quicker). They search thoroughly in every bag but they don't hit you that hard on duty.

Take for instance my last pass through customs. I only ended up paying $89BZ for about $2000BZ of stuff I brought in (Clothes, wireless routers, laptop, other electronics, wine, alcohol, cheese, a bunch of other stuff.) Not a bad deal for $89.