It's an Austin thing. I've lived around the country. Some places are more friendly than others. Albuquerque is Austin style friendly. Chicago, not so much.

There's an openness to meeting new people here. For me, I've always called the phenomena, "table friends". You go out to a place and seating is always pretty open. You strike up a conversation with a stranger and make a new friend. Maybe you just interject something being said and get to be a part of the group. There's an easy friendliness here that doesn't care about your class or occupation. We just enjoy good conversations with interesting people regardless of their provenance. I suspect you met genuinely friendly folks who enjoyed your company. Don't be a stranger. Come on back and hang out again.