They're passionate about the EU because they've been sold the cultural argument on 'Internationalism' and fallen for the lie that wanting a break from the EU is only the wish of little Englanders. I mean, they even believe all our workers rights are only thanks to the EU! They are sadly deluded.
Ah the old 'they only think that because' argument.
You only think that because you are a bit older, feel you have lost out a bit in life, and resent the naive vigour of the young.