Set both the primary party and the user rights?

Is there any reason to set both the primary party and the user rights to the same party?

alice <- allocateParty "alice"

aliceId1 <- validateUserId "Alice1"
aliceId2 <- validateUserId "Alice2"
aliceId3 <- validateUserId "Alice3"

createUser (User aliceId1 (Some alice)) []
createUser (User aliceId2 (Some alice)) [CanActAs alice]
createUser (User aliceId3  None       ) [CanActAs alice]

I would think that Alice1 is the preferred pattern. Is there any reason to use the other two?

IOW, would there be any difference in result when submitting commands as aliceId1, aliceId2, or aliceId3?

Apparently, the user rights must be set, even if the primary party is set.