I've actually seen titles being used in very different way, as a form of currency. You can offer people a lower salary for which in return they get a big inflated title to stick on their Linkedin profile. Loads of people love big titles to prance around with (especially the younger ones).
I wonder if it ever occurs to these people that I can still see (on linkedin) that you're a "senior javascript engineer" who just graduated from college 2 years ago. 2 years ago you really were a 'senior', but now it's just title inflation?
I also wonder if these same people assume everyone else with "senior" in their title has as little experience as they do.