rinse aid is for hard water. restaurants probably tend to not treat the water and the commercial dishwashers they use probably tend to not have a provision for salt. they operate very differently than your residential dishwasher.
So yes, completely unneeded if you have soft water. Most dishwashers don't have a provision for salt.
I have hard water and a dishwasher with a softener. The plates are dramatically cleaner if there's salt in the softener, no matter what detergent i use.
rinse aid is for hard water. restaurants probably tend to not treat the water and the commercial dishwashers they use probably tend to not have a provision for salt. they operate very differently than your residential dishwasher.
So yes, completely unneeded if you have soft water. Most dishwashers don't have a provision for salt.
Also completely unneeded if you don't mind spots.