It's a trade-off between features. A smartphone does much more than a traditional phone: wireless, 3G, and most of all, high resolution screens make the high consumption a necessary evil in order to deliver the added functionalities.
Personally, I can't really see the added value of having to plug my smartphone less frequently than once per day, as opposed to have all the features offered in exchange.
Power consumption only tells only part of the story : it should be compared to the features offered by the phone, and in which conditions. I doubt we are talking about 48 days of standby with wifi and 3G active, that would be how you normally use a smartphone.
I agree that having more features for a cost in term of battery life is a good trade-off. Still, the battery life argument is a good one when considering buying a new phone.
Between different brands and models, you see a huge difference in term of battery life (think Motorola Android phones VS Apple iPhone 5).
I see as an advantage not having to charge my phone every night, I like knowing that if I forget my charger when travelling, my phone won't be dead after a single day. This is just my personal experience, some people call a lot, some people go on the Internet a lot through 3G (and most phones out there won't last the entire day doing that), or simply the fact of knowing that after a few months of usage, my battery life won't be down to a few hours (yes, battery life goes worse with usage).
