Why did Michael "never take Joanna as a commuter"?

At the end of The Commuter (2018), Michael is back on the train station, and he approaches Joanna:

Michael: The 6:20 every morning to Chicago, the 5:30 home, you know I never took you as a commuter.

Best Answer

I haven't seen the movie, so I may be missing some important context, but in general, saying "I never took you as SOMETHING" means "I didn't think you were interested in SOMETHING"

For example, "I never took you for a golfer" (after discovering that a person plays golf) means "I never thought you were the sort of person who'd enjoy playing golf."

So, based on what you've put in the question so far, I believe Micheal is saying he didn't think Joanna is the sort of person who would use public transportation (apparently having just found out she does so every day.)

Note: the term "commuting" does not always refer to public transit, but in this case as he's referencing train schedules, I would think it does.