I know, and they will only go about 6 weeks on the 6 batteries. It's not too bad though if you only pay $1 a battery. Which is what they are at Costco. Last year I was getting the Rayovacs at Wal Mart, 6 pack for $6.00 but I see the price has gone up now.
I also have an external battery that I use with my D40's. It will go a long time on it. The D40's will really suck the batteries down in cold weather, so last winter I used a deep cycle marine battery and ran it for 3 months on that. It was great. But only reason I could do it is it was only 100 yards from the road. That battery was heavy!