I don't understand this thinking. Just like a daily pill is easier to remember, it's easier for me to plug in my iPxxxx every night before going to bed. If I had to remember every third day I would eventually forget (like I do my BB) and wind up somewhere with a dead battery.
Although a slightly longer battery for those heavy usage days would be good.
I don't need a battery that lasts 3-4 days but I would love a battery that lasts 24 - 36 hours with moderate use. I have a charger at my desk but some days I'm in meetings all day long and by the time I leave for the day my phone could be under 50%. If I go to my girlfriends house and spend the night I may not have any battery left by the morning. If I had a battery that lasted 3-4 X longer this wouldn't be an issue. I'd still charge it every night at home but the night's I'm not home I don't have to worry about it.
Here's another example. I go to a baseball game after work. Same scenario, I'm at 50% when I leave the office and my battery could be dead before the game is over with light to moderate use. If again, I don't go back home after the game I have no phone the next day unless I can plug it in for a while at work. I shouldn't need to leave the office with 100% battery to make it to the next morning.
These phones (all smartphones) are made to be used. The commericals everyone shows don't include the phone plugged into a charger. Talking, texting, email, surfing, facebook, twitter, games, news, all drain the battery. Sure I can get the phone to last a full 24 hours. That is if I don't use it. Even if it's a non eventful day, 12 hours can be a challenge.
I'd much rather have the problem of forgetting to charge my phone and running out of battery than having the peace of mind that I can go more than 24 hours on a full charge without praying my battery doesn't die.
Throw 4G into the mix and the drain is 50% or more faster. If my battery lasts 10 hours on 3G, go to 4G and we're down to 4-5 hours. Make the battery last 4 X longer and now we're back up to 16-20 hours. I don't think that's asking too much.