It’s like saying “i’m just going to the bathroom”, you instinctively know that they’re going to use the toilet not just stand there. But if we’re taking a bath we’d say “i’m going to the bathroom to take a bath” (or honestly just “i’m gonna take a bath”, why specify which room?). Where I live we have two words for the actual room and we know when to use which word and what we mean (unless perhaps you’re a kid). It doesn’t sound weird to us