Our dog regularly eats the cat food - morning and evening especially. Dcat 1 will sniff the dog food and sometimes have a taste, which then prompts DDog to rush through and devour the food he was previously turning his nose up at. I'm pretty sure the dog eats more cat food than the cats do. I believe dog food isn't good for cats.
My old cat used to love Butchers dog food, I think it was the tripe he was attracted to and I'd often find him snacking in the dog dishes with two labradors desperately watching and flooding the kitchen with drool!
My main issue is the dogs stealing the cats food, I have five cats and had to build a special box so that that the cats could get in and not the dogs, we used an Ikea storage box which worked well until one of the dogs managed to get it stuck on his head during the night. We now have a vinyl cover on the dining table and feed the cats on there, one is too timid to eat in the kitchen. I still regularly find empty dishes and happy dogs with the tablecloth dragged practically onto the floor.
My dogs would eat the cat food, so we have a stair gate on the kitchen door - the cats have free access to dry food, and two of them like to eat their wet food over the course of the day. Dog food is inhaled in under two minutes, so no chance for cats to steal it!
my cats consider what the dog has left in her bowl as seconds after they have finished their own food,
but i have to sit and watch whos eating what in a morning because the dog will eat half of hers then shove the cats out of the way and eat everything going in the cat dishes,
so i have to wait till she has eaten her fill and then put her outside for a few minutes so the cats get their share of their own breakfast and any biscuits they leave in the afternoon are dibs for the dog if i dont watch her