Babs,
Reports like this (on energy savings) is averaged out based on many or just several 'known' products.
For instance most of these reports do not account for new appliances, they make the assumption that you are using a 10+ year old (conventional not convection) oven/stove. They might also use non-energy-star appliances in order to up the ante on the numbers. Again it is averaged out, yes you may have the highly energy efficient electric oven, but your neighbor may be using an early 1980's conventional electric oven that sucks power like there is no tomorrow.
slow cookers also come in a wide variety of wattage - and while the newer ones may use less power, again the average takes into account that many folk have an older, more energy burning model.
The price is averaged out, while you may be paying .065 cents a kWt - others may be paying a hella lot more.
In 2008 the price ranged from 6.7¢ in Idaho to 30¢ in Hawaii
http://michaelbluejay.com/electricity/cost.html I believe Ladies' home journal is an international publication, thus has taken into account the price range on average over a much larger area.
While that one breaks it down by US states, I know that folk on the other side of the river (who get their power mostly via natural gas instead of the dam) are paying 2-3 cents more than we pay - simply because they are in Modesto Irrigation district (supplies power, not PG&E that only supplies gas out here) and we are in Turlock Irrigation District.
Are you missing the point? No - you checked, you sat down and did the math against the appliances and power service you have.
The point was (is?) that in many instances slow cookers cost less to operate than your oven - of course the article may not have clarified for everyone that these figures and numbers are not just pulled out of thin air, and are based on an average including a wide range of power regions and forms of oven and slow cooker.