Definitely DO NOT do that! This isn't the midnight express. You're not moving large quantities of heroin. This is like a traffic violation. The person that collects the money is different than the customs agent. The penalty is 1000 pesos, just go pay it on the right side (or get directed by customs), then go back in the normal line. No need to try to be cute, this could cause you more problems.Just put 500 pesos in your passport when you pass it to the person at immigration.