Why would we need them? People need all game files to run our client, which includes meshes. The client can already extract and read them from their original formats, so there's no point in converting them to an alternate format either...
I don't know what you're getting at, but we already know how to handle mesh files perfectly: http://wiki.niotso.org/MESH They are currently read to render sim characters in SimAntics Debug and CAS.