Ask her to think a little about how cats eat in the wild. They can't "graze" like horses or cattle (or even humans, who descended from primates who snacked on vegetation off and on all day long).
Cats do not gorge/fast to the degree that canids do (a wolf pack may bring down a caribou once in 3-7 days, gorging themselves on up to 21% of their body weight!). Instead, since they hunt alone, their prey is small. They may kill twice a day, occasionally 3X a day. There is no handy snack feeder out in the wild.
The canine and feline pancreas is not set up for constant use. Forcing it to work overtime via snacking (and even walking by th kibble bowl and smelling the food can trigger it to launch into high gear) is one thing that can lead to diabetes, as can the carbs in kibble.
Even when I DID feed kibble, I never free-fed. My cats have always eaten twice a day (adults, that is--kittens, of course, eat more often). For cats used to having the gravy-train available 24/7, that's the hardest transition to make, and often getting the cat used to meal feeding first (using the food they are already familiar with, be that kibble or canned) is the best way to proceed. Once the cat is used to eating meals twice a day, then you can transition to raw (using canned as an intermediary if necessary).
Will the cat sometimes be hungry? YES!! And thatís a GOOD thing. Hunger means that you enjoy your food and eat it heartily, rather than nibbling half-heartedly. A great thing to do before meals is to play interactively w/ your cat Ė with a Cat Dancer or Da Bird toy, simulating hunting. Then, when the catís food is presented, itís as if he made a kill. The end result is true Satisfaction.