As I recall on Voyager with a little coaxing Tuvok was able to use the holodeck to get “relief” so I’d imagine the same goes for most vulcans who might be on long away missions
To be fair, there was an episode of KotH where Bobby and Peggy discover that charcoal was actually superior to propane when it came to taste. It was a whole big thing and hilarious to watch them try to keep it a secret from Hank lol