I'm just positing or rather just musing to myself how the "me" came into being. It's not like I believe it to be an article of faith or anything.

But I bought me a ____ is standard usage in certain dialects. Whether or not those dialects are highly esteemed is another matter, but there are regular rules for such in those dialects. In fact, my learning how to use reflexive verbs in Latin and Spanish was much easier because of how the pronouns are used in many Southern expressions.

But what do I know? I use one dialect when writing, a similar one when speaking with certain people, a second dialect with another group, and sometimes a third when communicating with some of the local yokels. Keeping up with the grammatical rules for each is exhausting