In studies of real language, "there's + plural" predominates among all levels of speakers.
Grammar is not some fixed set of ironclad rules. Grammar, in its real sense, its real meaning describes how a people actually use language. It really can't be any other way for there is no way to determine correctness than by checking to see what the majority of language users choose for a given situation.
Fixed rules are called prescriptions and prescriptions have never accurately described language. Prescriptivists have a little out for themselves; they say that there are always exceptions. That's true. What we find is that a prescriptivist's exception often is the real rule.
Student or Learner