I'm thinking about taking a disabled student's seat in class.
But he needs that seat. Why are you thinking of taking it from him?
I've been here since 4 am and he just came
It's understandable that you feel you should have the seat since you were there first. However, you should not take a seat from a disabled person. Instead, you should show compassion and find another place to sit.
Eh, I don't care. He's just disabled. That doesn't make him more deserving than me.
He might be unable to sit in another seat that isn't intended for disabled people, or he might not be able to stand for that long due to his disability. By depriving him of his seat, you might be taking away his chance to stay in class and learn. You might also be forced to move, which would embarrass you in front of the class.