I buy olive oils that taste good to me. For everyday cooking, I use California Olive Ranch. For salads or dipping or any dish where the oil flavor really matters, I try to find a nice arbequina or a fruity, peppery blend (the one I have in my pantry now is from California, but I’ve had others from elsewhere). I wouldn’t waste a super expensive oil on everyday frying, though. I made imam bayildi the other day, and because it requires a lot of oil, I used Trader Joe’s and it was fine.
I don’t know whether I use more olive oil than the average American, but I also use a ton of butter, especially in baking.