No reason to agitate them or to let them agitate me. Letting them pass doesn't really hold me up in any way so why do I care? That being said, people who tailgate constantly are horrible human beings. I've had plenty of experiences where people tailgate - not because they are trying to push you to go faster - but because they just like following people that close in general. It's idiotic and dangerous and one of the common reasons for accidents on the roadways during high traffic times.