'Bag' a seat? For god's sake!!!

Maybe his bag was very heavy and his legs might break if he put the bag on his laps.

Maybe he has some infectious disease and his bag can prevent people from getting into close contact with him?

Maybe he is blind and didn't realise the bus was packed?

Maybe he is just BLARDY INCONSIDERATE????

*ps: for those who cannot see the picture, his bag is taking up a seat