Up untill a little over 3 years ago I very seldomly went on buses, but never noticed anyonyone thanking the driver back then.
Then 3 years ago when I started using the buses on a regular basis I noticed that everyone seemed to thank the driver and wondered myself "When the fuck did people start doing this?" so I started too.

It does piss me off when they don't acknoweldge you back though, and the ones that look at me like I'm a piece of shit because I have a free bus pass.
( The invisable man Is having a long lazy soak in search, Mon 3 Jun 2013, 14:49, 1 reply)

most of our local drivers will acknowledge it
but there's always a few arseholes
( Smash Monkey lowering the tone of the whole internet, Wed 5 Jun 2013, 14:14, closed)