This is not because Vereen and Quiz are similar players, per se. Vereen is actually bigger than Quiz at 5'10 and has carved out a small but important role on this Patriots team, and he flashed the ability to cause mismatches when lined up as a wideout. Quiz is not as fast, but he is extremely agile and punishes defenders more than Vereen.
Now that we have the differences out of the way, why line Rodgers up outside? The short answer: Because it makes the offense more dynamic. The long answer: Because Rodgers has quality hands, because he can make plays in space and because the Falcons aren't exactly thick with top-flight receiving options once you get down the depth chart.
Lining up Rodgers in four or five receiver sets would force the defense to cover him with a linebacker or safety, and Quiz has shown he can straight up embarrass players at those positions when he has a chance to make a move. This wouldn't be a common occurence, per se, but having him out wide perhaps 15-20 times during the season could lead to a handful of devastating plays.
Would you give Rodgers some snaps outside?