Do some kids never learn how to ride a tricycle?

If she loves the thing she already has then why worry? Doesn't matter the age range of the riding toy, it is just what she likes. Whatever you get her she may not like, so I would not buy her anything else, riding wise, until she plays with the trike some. When she learns to do the trike and enjoy it (and she will one day) then I would get her something else after a while. No big deal, let it be.