First, if the token is easily accessible, then they can steal it even if they don't actually look for it. Like, steal "accidentally". Second, obscurity here is

First, if the token is easily accessible, then they can steal it even if they don't actually look for it. Like, steal "accidentally". Second, obscurity here is an important part of the security: you don't have to tell anyone that you have a token in the wall, so even if they came specifically for the token, they can surely look for it in your home (because the majority of people store backup token just at home), but it's a lot less likely that they start break walls (unless they specifically know it's there). So here, the level of security is up to the token owner. As to having to take a sledgehammer: well, losing a token is an emergency situation and I just try hard not to lose it. But if I do, I still have a way out, and breaking a wall a little is still a lot better than losing the access to my accounts.