My wife and I ran an experiment to find this out on our cat, too.
He already uses his paws to reach into several narrow cups to pull out food; so this was nothing out of the ordinary for him. What we did was, put food in 1 cup and watched as he continually used his left paw. Then, we rotated the device so the cup with food was against the wall and difficult to reach with his left paw; hoping this would force him to use his right paw. Wrong. He rotated his body and walked to the other side so he could use his left paw. We rotated again as did he.
We've done this several times now and he always moves his body instead of just simply using his right paw.
Deborah Wells and Sarah Millsopp should seriously consider teaming up with the guys who patented a method of inducing aerobic exercise in an unrestrained cat.
That was the author's next point, that the cat knows she doesn't have to work too hard to get the food, as the human will make it available in short order.
Better story in the linked original article in New Scientist: https://www.newscientist.com/article/dn17510-is-your-cat-lef...
And the abstract of the original study, since the whole article is behind a ridiculous paywall, part of the typical Elsevier scam of blocking science: http://www.sciencedirect.com/science/article/pii/S0003347209...