Do you find the environment harsher on your equipment and it rusting or sticking without regular maintenance?
Not to any concerning degree. Unless you're leaving the gear on the wall for weeks or months at a time, you wont need any special maintenance procedures. Inspect the gear on occasion and wash it if you feel the need to, but otherwise you shouldent have an issue. If you leave some project draws up on the wall for a few months, that may become an issue.