I've often seen people on the internet make fun of fat people on bikes and wondered "What's so funny about that? How does people who think that's funny get around?"
Then I leaned that The Netherlands and Denmark are the "weird" ones, because here everybody casually ride bikes all the time, while most other places it's considered something you do if you can't afford a car or if you're a health freak.
So yeah, if you want to see lots of fat people on bikes, just visit The Netherlands or Denmark. You'll be pretty desensitized to it after a few days.