In the past, I've had to make two mercy flights from FRA-SYD. When I checked in, I asked for somewhere quiet. BA gave me a whole row to myself. By doing that, they bought my custom for many years. Those days are gone.
If I can bung them £50 for an exit seat on a 744, I'll happily hand it over. If they want £750 for an upgrade from PE to J at check-in, that's great - even better if they'll haggle.
As other posters have said, hark back to the days when you checked in as soon as you could in order to secure your seat. How much is an hour of your life worth?
The OP might reflect for a moment on the 'green' taxes he's paying when he flies. The seat selection stuff, as The SSK points out, is compartmentalisation of costs. It's transparent and it opens things up to the market.
SO