Have you tried a wooden box with a cut out for a steel bowl to sit into? It wouldn't have to be very tall, but bigger than the bowl, no matter what size bowl you want to use. If the entire box gets dumped, add an L-brace at each end of the wooden box and attach it to the woodwork. You can still remove the bowl to clean and refill, but the box won't be going anywhere. If you need to remove the box eventually, the two little screw holes are easy to repair.