Is there some sort of bus club that I am unaware of? Do people who don't regularly take the bus have a certain look about them that daily riders are immediately privy to? I have a car and a bike so my transportation is usually spoken for. This means a few things:
I do not have a bus pass that allows me immediate and hassle free boarding.
I am not immediately aware of how the bike loading contraption on the front of the bus works, though I will eventually figure it out.
When I do take the bus, it is usually because I am going to the airport and therefore have an obnoxious amount of stuff with me.
These three things are a general equation for other more seasoned riders to become quickly irritated with me.