No car, plane rides or children. I also eat less meat than average, rarely buy new (or used) stuff and vote for one of the greener parties.
I grew up (first world) poor, so this was just the way things were, when I was a child. My income is still quite low but I could absolutely live more lavishly than I do now, if I wanted to.
I think school/work days would be shorter and more intense. Small talk and chit chat would not be an integrated part of a work/school day, but instead something that happened before or after school/work if you wanted to. A meeting wouldn't start with 10 minutes of "how have you been?" or random jokes, but instead jump right into business. Working from home would also be more common.
Having a niche hobby or working with something niche would be way more common, and hobbies would be viewed as more important than they are today. People without any hobbies or interests would be viewed as really weird.
Practical and comfortable clothes would also be more common, and fashion would be more erratic/varied. Pop culture would be less of a thing.