So sometime I take my bike with me on my way to work and in my city, there are special compartments at each end of the trains where people with bikes should ride. So these compartments still have seats along the walls of the compartment so that people can sit there, but once you enter with a bike you will  block 2 or 3 of the seats. So if people want to use the seats, you have to move your bike a bit so they can reach the seats and sit down. Which is most of the time not a problem, neither for people with bikes (like me, who gladly let people reach the seats) nor for people who want to sit down (who wait the bike is moved). 

So one day, there were quite a lot of people already in the train and one seat behind my bike happend to be still empty. After the train stopped at the next station, an old lady comes rushing into the compartment, sees the empty seat next to me and immediately almost yells at me to make room at this very instant so she can sit down. I am bewildered and don't react right away because honestly, normally people politely ask you to let them in and I would never, ever refuse to do so. But being bewildered by her rudness I (before making space so she could sit down) said to her that I have no problem letting her reach the seat, but that I find the way she talked to me very rude, and since this is the bike compartment (cleary stated outside) it will happen that there are bikes blocking seats and that it might take a moment for people to make room. She was pissed at me for telling her that she was rude and a lot of other people around me started to be pissed at me as well, because "she is just an old lady wanting to sit down". 

The thing is, I would never ever not give up my seat for an older person or person more in need of a seat than myself and I would never ever not make room with my bike so people can reach their seats. But still I think that the way she talked to me was not ok, and it was ok for me to point it out although most of the other passengers seemed to think that IATA.