Obviously, not every Native American dwelling is a tipi. Conversely, non-Americans may construct tipis (though they would probably not call them that, nor would all native Americans, which seems like an opportunity where you could inadvertently use the wrong word). Also maybe not everyone knows the difference between a tipi, chum, yurt etc. (and one real difference is simply the language of the nomad in question, so talking about teepees with a Yupik may be another kind of faux pas)