People also forget about little things like laptops and such, where extraneous power usage is more than just a little higher electric bill and environment hostility. It actually decreases how long you can play the game for on an plane or train or automobile. (Or boat, zeppelin, gondola, etc.)
You can easily see the difference between an experienced and intelligent game developer and ones who think like you when you play games on an iPhone or the like. I have played gorgeous 3D games that let the battery last a good 6 hours and I have also played silly little 2D games with no crazy effects or anything that drain the battery in 2.5 hours.
A game's simulation has a maximum rate at which it needs to run. Twitch-heavy shooters and even most other action games usually want to peg out at your monitor's refresh rate, but many other games have no need to run any faster than 30 FPS, and then only for the sake of maintaining some UI/character animations while waiting for player input.
Even for twitch-heavy games like the Quake-based games, there's no need to run any faster than the monitor's refresh rate. I keep hearing "pro gamers" (read: losers whose knowledge of game internals and hardware comes from gamer forums filled with other clueless losers all parroting each others' old wives' tales about performance and latency) talk about how the latency of vsync hurts their games, but that's just a load of crap. The maximum 1/60th of a second of latency you might get is dwarfed by 1/20th (or higher, in many cases) of a second of latency that exists between user input to visible output that even the best gaming PC still has. Usually, people complaining that vsync causes latency are people who don't always win, refuse to accept that they're not the God of Gaming, and scapegoat everything they can: they'll end up turning off every feature and spending $1,000's on high-end computer equipment, and then just continue to yell and scream every time they get fragegd that their Internet connection lag-spiked or they got distracted or the other guy is hax0ring. They're pretty much only happy when they're fighting other gamers who are really good but not quite as good as they are, thus making the game appear challenging even though there's a small chance of losing. You see similar people in non-computer games as well, like amateur sports teams or the majority of US martial arts dojos. Not people you should listen to. Ever.