ang moh power! yeah!
ok seriously, screw the expat (ang moh?). it's his stupidity that he bought food first then find a seat. it's his stupidity that he thought we singaporeans are easy prey. it's his stupidity to argue with hawaiisg bro (aloha!).
why we chope seats with tissue paper? has anyone thought of that? i do not think that it stems from selfishness, but rather it stems from typical singaporean pragmatism. everyone wants to enjoy hot food. we wouldn't want our food to turn cold while waiting for a seat. also, the risk of someone losing control of the tray (and worse spilling the food onto someone else) while waiting for a seat can be disastrous. so our culture of choping seats with tissue paper packets and umbrellas etc etc has evolved from pragmatism.
and to that expat / FTrash, you can go sod off.