One of these cans is not like the other. (Hint, take a look at the bottom of the can.)
Shaving cans for decades have used the same material for the bottom of the can as the rest of the canister. Steel…which contains iron oxides in it. So as steel gets wet it releases those oxides as rust which ruins tile.
Recent improvements to can “technology” include making the same cans with aluminum bottoms. Aluminum doesn’t really “rust” per-se. Aluminum when exposed to water and air actually creates its own protective covering which prevents it from rusting. As an element it is much more susceptible to attacks from chlorides such as salt / salt water.
If your tile already has damage done to it by rust you can try cleaning with a mild hydrochloric acid such as a Lysol toilet bowl cleaner or CLR (calcium, lime, rust) remover.
Once it’s all clean, spend the extra dollar for an aluminum bottom can. Your scrubbing arm will thank you. …High five!