Even if this were not the case, the more regulation added to bitcoins, the more people move to alternative crypto currencies. I don't see people seeking to regulate litecoin, dogecoin, coinye, etc.
People aren't calling for the regulation of other cryptocurrencies mostly because they don't have the same kind of usage and economy surrounding them that bitcoin has. If people start trading coinye in the same way and it reaches similar volumes as bitcoin, you'll see the same sort of talk. It just makes more sense to treat cryptocurrencies the same under the law, unless there is something about a particular one that made it most different than all the other current variations.
Like when my parents refer to all videogames as "Nintendo".