If it were a full flight, and you were a middle seat passenger in my row, I'd probably be moderately annoyed if you were eating a big sloppy cheeseburger. And if you had anything less than 12 year old British boarding school boy table manners, I'd probably even say something to you about it.. I swear to god, if one of those onions falls out of that burger and touches my leg, you better know how to fight..