Alias Method Chain

Why doesn't [ActiveRecord::Base#arel_attributes_values](https://github.com/engageis/activerecord-postgres-hstore/blob/master/lib/activerecord-postgres-hstore/activerecord.rb#L75-L91) use alias_method_chain? Seems that would be less intrusive so other gems (like [activerecord-postgres-array](https://github.com/tlconnor/activerecord-postgres-array/)) could do their business in that class and method without business like [this](https://github.com/tlconnor/activerecord-postgres-array/blob/master/lib/activerecord-postgres-array/activerecord.rb#L19-L20).

I'ma start hacking on this now but was wondering why it wasn't done already. Anyone have any pointers?