G'day John,
Mate, I wouldn't stress too much over the marks mate. You can allways paint it. Your boat is looking really nice mate.
Jack, the basterds here do that sort of stuff the time. especially so with a 'new customer" A local big name hardware chain is actually renouned for it. Unluss you actually carry your tmber or ply out to your car at the moment of selection, it often look "inferior" to what it ws that you selected.
I choose to buy my ply in bulk from a major ply and panel distributor. I also buy a lot of ply and panel MDF for my work from the same mob. Even with the volume that I buy, both for myself and the big orders for my work, there are allways the odd panel or two or three that are second grade. A major pita but it is pretty typical of the way a lot of Aussies are doing business these days.