What type speedo is he wearing??

[PSDave]

That seam is there to accommodate the male anatomy. I prefer some space for my junk and not have it smashed in a flat front suit. To me, it looks more natural and is more flattering. But to each his own.
I was curious and looked at the nylon ones I have like the one in the film cut and they are both all nylon and flat front. Checking my nylon suits, there was only one with a seam in the front - a buckle on number I got from Nu-Parr years ago.