No rinse aid for me thanks. I use white vinegar in the dispenser where the rinse aid goes.
It’s cheaper, its a food (not harsh chemical) and most importantly it’s non sudsing.
The dishwasher detergent has anti-foam agents because milk and eggs can create foam.
So why add a foaming rinse agent? I have had quite a few people pay me to come clean up after a jet dry incident gone wrong (spill, leak or malfunction resulting foam all over the floor).