Saw this interesting pier cart at the Oceanside Pier the other day. The one problem is that it would only work on piers with easy straight forward access to the pier. Some piers require climbing steps to the pier and it wouldn't work.
That's pretty creative. I like the use of repurposed materials. Though there aren't many piers up in this area, the river is often a trek from parking. I might need to come up with something like that (but with beefier wheels) to haul my gear.