I'm not going to give up my seat to a family at an airport business lounge
Why wouldn't you give up your seat?
Because I'm tired and want to sit down
It's your right to sit your tush right on that seat. You are not obligated to give up your seat to complete strangers anywhere.
But I was raised in a certain way so I don't feel like it.
When it comes to chairs its typically first come first serve. If someone else has some kind of disability though its kind to be considerate of others and share your seat with them. Wouldn't you like someone to do the same for you?