Dishwasher additives are generally silicate based to raise the pH and hence cut through grease. These can leave smears on glasses and may be responsible for wear on glassware. It may alternatively be mechanical action in the machine that causes the wear. Rinse aids are surfactants (detergents if you like), designed to lower surface tension and make water run off rather than stick and bead.
I have a couple of friends in the detergent industry, you'd be surprised at how crude it all is and how few actual ingredients there are. If you don't think correctly chosen household chemicals can do the same as bespoke RCM chemicals, then you are naive. The difficulty is selecting the CORRECT houshold chemicals. None of us want to have to dig Persil off a record. The rest of it though is common chemistry, it does a job the same way that different brands of soap powder do. The chemistry involved is so advanced that my pal does it in his garage and then brings it into the kitchen to try it out on the washer/dishy/floor before marketing it.
