I have stopped robbing by setting up a sprinkler  on the hives and
reducing entrance size down to about dime size. All manner of other things
pop up in the literature from making a screened entrance the bees have to
learn to propping an old window in front of the hive, to removing all the
hive covers and sending everyone home to guard their own.
   The sprinkler and reduced entrance worked for me- best not to get it
started.
Snotty dispositioned bees seem to rob more or are snotty because they rob.
The snotty bees with the extra super probably got it by robbing.