There may be designs that cut out some/most of the cost, but I made the comment because I watched a YouTube documentary on an airport that was making modifications and they had to dig up a bunch of the runways. They made a big deal out of the work, including working with a special contractor who had a practice area where they tried all the work they'd have to do ahead of time and timed themselves to be sure they could get the runway back in operating condition by the time it was needed. The amount of work they went through for something fairly minor was pretty memorable. I took from it that airports have a lot of logistical concerns that are pretty unique and the "that seems simple" take that I'd previously had about the tarmac portion of an airport being just a bunch of asphalt with some signs and lights on it was totally ignorant of all the complexity.