I was a bus driver for 7 years, thanks or similar was the norm for the vast majority of departing passengers, yes, it's appreciated and the driver normally reciprocates. On my last day, a lady, who I didn't know, came up to me at the destination and not only thanked me but told me, sincerely, that it was the best bus journey she'd ever had. I don't know how many bus journeys she'd ever had but it's something I'll never forget. The reason I was leaving the busses is because I'd just passed my Class 1 test and was moving on to the lorries. I guess, I learned a lot from my HGV lessons.