The path there goes through a wetland. I thought the pavement treatment was odd there at first, too, but then I realized they used permeable pavers to facilitate water run off. I think they are just trying to make the path as much like the ground as they can.
2011 Jamis Quest "Cy"
2009 Trek 7500 "Diesel"
2008 Rans Stratus LE recumbent "The 'Bentley"