It depends a lot of how the mask looks. By emphatizing or covering some traits some masks can look funnier, creepier or even more stylish. Of course when it comes to mask designs if you wanna avoid the creep factor, look up for the uncanny valley.
As @skicoak mentioned before, context is also important
For example, in a costume party or a mascarade, masks are expected. If people go on a meeting wearing masks, they will give the vibe of a cult or secret organization. If they fight crime wearing masks, they may be superheroes or vigilantes.