Maybe The Dog Just Thinks They Are An Idiot

Some unknown co-worker offered these cans of dog food for someone to take.  Click the picture to enbiggen.

In case you didn't enbiggen, each of those are something and rice.  Rice.  A grain.  The phrase "grain of rice" falls just below "grain of salt" in the "grain of..." idioms.  Why would this person even add that anyway?  I didn't flip the note over but it probably said "vegan and GMO-free as well!!!"