A pre-main street extension showed that even at its shortest the streetcar wasn't just for “fun”:

Nearly 40% of regular riders use the KC Streetcar four or more days each week.

In terms of trip purpose, 31% of weekday streetcar riders reported utilizing the service for employment-related trips.

That number has probably gone up with it now providing more commuter options with the increased length.

Would all of those riders have taken the bus otherwise? Unfortunately, probably not. But it also doesn't have to be a zero-sum game. The streetcar isn't killing our buses and we shouldn't have to chose between one or the other. Kansas City deserves a reliable public transportation system that involves multiple arms that solve different needs.