I am sick of my cat's stealing habit!

Your cat seems to be very food motivated. Do not expect any negative reinforcement to ever work to keep it from stealing food, because as you said, as soon as your back is turned it will do it because it's getting a huge reward. That means don't bother spraying, yelling, and so forth.

The biggest thing is to never leave food unattended or unprotected. All food needs to be stored in places that are inaccessible to the cat. If it figures out how to open drawers and cabinets, then you may be forced to get child proof locks on your drawers and cabinets. Use breadboxes and Tupperware and so forth for food that does not need to be refrigerated. Do not thaw food by leaving it out on the counter, but rather thaw it by transferring it to your refrigerator, which you should be doing anyways for food safety reasons since the outside of the food will thaw before the inside if simply left out, and dangerous bacteria could grow on the outside of the food.

Definitely do not ever leave food unattended. If there are multiple people in your household, you can request for them to guard the food if you really must leave it unattended for some reason. If there is not, you just have to be more strategic about how you go about preparing your food. If you know you're going to want to wash your hands before you eat, leave your plates in the kitchen, wash your hands at the kitchen sink, and then bring your plates to the table for eating. Then if your cat attempts to steal food, simply gently grab the cat and place it back on the floor. That should be enough to demonstrate that there's no point in attempting to steal food while you are there, because you'll always intercept it.

For dirty dishes, you'll just need to clean them as soon as you can rather than leave them to sit and attract the cat. You could even have one person in the household prepare the food, and another person in the household help out by cleaning as dishes are being dirtied. Then there will be no chance at all for the cat to try to lick dirty dishes.

The other thing is, if your cat just sits by the fridge all day, that is probably a sign it is very bored, and because it is so food motivated, it is alleviating boredom by trying to eat. I recommend you trying to entertain your cat a lot more also. Do more interactive play with it, encourage it to look out windows by placing cat furniture by them or getting bird feeders. Instead of one of its regular meals, you could give it that meal inside a food puzzle toy, so it has to work for its food. Be creative and do what you can to get it doing something else other than staring at the fridge.

The last advice I can give you is that you can also give it it's meals at strategic times, for instance, feed it right as you're about to sit down to eat. That way it'll be distracted by it's own food.

What are you currently feeding them? Because what you're describing is very common especially in cats that are dry kibble fed. This can also happen with an unbalanced diet and/or feeding a low quality commercial canned food. Protein needs of felines are very high as they are obligate carnivores and may always be hungry and overeating in an attempt to meet their requirements for essential nutrients. Dry food rarely if ever contains enough protein even though current guidelines recommend it and package labeling shows the required content listed. It certainly lacks necessary moisture for proper hydration which could also result in overeating. Food preference and satiety are ultimately driven by nutrient density.

I also have a cat that does this. He only does it if you're not looking or are not present in the room. I understand how frustrating it is. My cat still does it, but not as often now. I gave my cat his own room with tons of toys, a big bed and a nice window to sit by. When we are not home or sleeping he is in his room, so he doesn’t cause trouble and destroy the house. I also find that tape on the counter works the best, as spraying water or getting angry at him doesn’t work. I give my cat one can of cat food a day. Never feed dry food. Hope this helps