Airlines engage in price discrimination to get as much money as they can from customers. This includes multiple strategies, most obviously classes of tickets.

For customers who want to (or can only afford to) pay less, you can get a basic economy ticket, without refunds, exchanges, nor seat assignment.

And on the opposite end, for customers who can pay more (often on their company's dime), you can get a business class ticket, with big seats, big thanks, and big contempt for the riffraff behind (i.e. below) you.