I thought that all travelling couples did this. I compare it with being allowed to change the door that you can open on a TV show. The costs of choosing two sid

I thought that all travelling couples did this. I compare it with being allowed to change the door that you can open on a TV show. The costs of choosing two side-by-side seats are greater than choosing just one seat, except for the extra room row. It also depends a bit on the length of the flight. Longer flights make you pay more for choosing a seat.