Someone didn't read the memo

Today's test question:
Look carefully at the photos below:

Now, look at this photo:

Can you spot the faux pas?

For those of you either old (like me) or otherwise not yet awake . . . 
a not so subtle hint:

Five riders in blue ONE in yellow/green . . . or whatever you call that.
Seems either a bit suspicious, a fashion statement, or simply did not read the memo.

And finally . . . the movie of the day!

Note how one unnamed rider seems to move to the front when
 he realizes the camera is on him.  no comment . . .