yes thats one reason they would not make a gezeirah but there are countless more
did they make a gezeirah that someone shouldnt blow his nose onto the street in public? i happened to see that a few days ago.
did they think that is okay.
we know what they thought about people who ate while walking down the street. they are passul from aidus. did they make a gezeirah?
ther must be literally millions of behaviors they did not think was okay but did not goizer.