DY: I hear you, and no I didn’t see the packaging. For someone who takes the time to look at the front and notices no OU symbol, then turns the package around to the back, notices 3 panels, one of which sports an OU symbol it may be fine.
However, I don’t think you have to be very stupid not to realize that the OU symbol is only for some of the food in the package. It may be a person in a hurry, a child taught to find the symbol before buying food. A dyslexic who can find the symbol but can’t read the packaging, a non English speaker who can find the symbol on the package. I’m sure you can come up with more examples.