CTPAT was all the rage when it first came out. Seemed like all the shippers only wanted CTPAT carriers, until DHS showed up at their doors looking to do an audit !!! Then for a lot of them, it wasn't quite so important.
The first audit is easy, but they get progressively harder (read expensive here). After our 4th, and final, audit DHS wanted us to spend over $200k to secure the property with fences, gates, lights, and guards. I asked why the guy down the road could get his CTPAT certification with a simple chain across the driveway. The auditors were unable to provide me with an answer. So we, (unceremoniously) let our CTPAT certification go. We opted to follow CTPAT procedures, and do the questionnaires instead. That was good enough.
It is 1,000% guaranteed that if there is a load "requiring" CTPAT certification, and there are no CTPAT trucks around, suddenly CTPAT becomes not quite so important.
No one, and I mean no one, pays you any extra to be CTPAT certified.