The idea that there's a general difference between Astros and Rangers fans, looks- or other-wise, falls in the general category of fake news. Like most things these days. Just the past 3 years alone, I've seen games in the following stadia: SF, Seattle, KC, StL, ChiSox, Pittsburgh, Nats, Yankees, Phillies, Red Sox, and the Os. I can tell you this. It doesn't really matter east coast, west coast or fly over - baseball fans come in all shapes and sizes, some as skinny as foot long hot dogs and others as fat as a big old plate of nachos. There are a lot of "relaxed" waistlines out there in MLB ballparks, and I don't just mean the pitchers on the field. And, no one cares.
What I love about the game though is the mutual respect that fans of all teams have for one another - I've gotten so many compliments for my Cards gear when I go to either Os or Nats games. Most recent version of this was that my son wore a new Molina (#4, a number destined to be retired in St Louis) jersey to Game 1 of the NLDS here between Nats and Cubs, and what that led to were all kinds of interesting conversations with mostly Cubs fans, like Heyward vs Fowler, or how many families had mixed allegiances between the two, or Maddon vs Matheny, or well you name it. And no one wondered why we as were there with our STL gear on. They just recognized that we were baseball fans, and this was the playoffs, and really what more do you need?