Stainless steel oxidizing with porcelain dishes, stoneware, etc.

Can Stainless steel cause white bowls to turn black on the inside of the bowl where the bottom of the bowl from one bowl has touched the stainless steel and then is stacked on top of a different bowl of the same size? When the bowl is removed, there is a black ring around the inside bottom of the other bowl. It appears to me that on these dishes the enamel has worn off. We live near the salt water and I am told the salt water, stainless steel and bowls create such oxidation and blackness on these dishes. I think this is all wrong and we are being misinformed. Can you help? We are asked to scrub these dishes each night with BonAm to be sure they are clean for the customers. I believe these dishes are just old and should be replaced, period.
Steel oxidizes with other metals, but not with dishes. I am not even sure Stainless Steel oxidizes. By asking you and you answering this question how do you know what you are saying is correct? I would believe you, if I were to bring this to my superiors how could I convince them that what you say is indeed true over the information they have gained that the bowls are oxidizing with the stainless steel?
Thank you in advance