'The popcorn arrives at a value', 'The popcorn just isn't free', 'The popcorn cost $ten', 'You have to pay for the popcorn' or, just, 'The popcorn is not free'. The statement, 'You may take your baby on the flight free of demand' would be in opposition to 'You should pay out to just take your child on a aircraft' or 'It's not free', or informally,