Thankfully one of the (many) joys of travelling alone is that generally I'll always be able to book an aisle seat even at the last minute "somewhere" so it usually works out ok anyway and if travelling with someone it's also great to be able to use that charge / rule as a great excuse to intentionally end up separated from them and so get a bit of peace to sit and actually WATCH an entire movie, or read a book without interruption or without having to make inane small talk for the sake of it !