But couldn't.
Levi is a title, and one that is held in esteem. Here's an Wiki article on Levites - for more information you might want to ask on the Facts board where people know what they're talking about. My knowledge is limited.
http://en.wikipedia.org/wiki/Levites
Interesting, though - I found this:
http://en.wikipedia.org/wiki/Levi - the information that it gives about Levi not being a name and instead being a caste for priests is the main reason that it's thought of as inappropriate. Levi is a pretty hefty title, I think.