Dogs do things that feel good to them. Being scolded by you feels bad, so your dog doesn't eat from the table if you're around. Licking up bread crumbs is tasty and feels good, so your dog does it whenever you're not around to scold him.
The first step is to change your own behavior:
- Both dogs don't get any kind of food or treat directly from a counter or a table. Never. If you have scraps for your dogs, save them until everyone is finished eating, then put them into their food bowls. They must unlearn that food comes from counters and tables.
- Measure as exactly as you can how far your dog can reach up the counter. Mark his reach with painters tape or other means that are easily removable later. Never ever store anything (not even a bread crumb) in the area your dog can reach. Push every single item behind the line. Jumping up the counter will no longer feel good if there's nothing to gain from it.
- Don't let any foot item stay on the table if you're no longer in the room. Either put everything back behind the line on the counter or put it into a container your dog cannot open (like a cupboard, drawer, stoneware or Tupperware container).
Without this first step, you'll never reach your goal. To aid you (and make your dog behave better in general), you should train "leave it" with your dog to improve his impulse control. Have a look at this video that shows 3 stages of the training: Basic understanding of the command, training in unusual situations and redirecting attention towards trained behaviors in real-live situations.
If that still isn't enough to completely stop your dog, you can make his behavior no longer feel good. It must happen automatically and every time. Different dogs react different to certain things, so you need to find what works best for your particular dog.
The problem with these methods is that they may affect your interactions with the kitchen furniture (by being sticky or standing in the way) and that if they fail only once, the whole training was utterly useless because your dog was once more rewarded for his naughty behavior.
- Dogs tend to dislike the smell and taste of lemons and tabasco sauce. Draw a line of lemon juice or tabasco sauce along the edge of the counter. When your dog tries to lick up bread crumbs, he'll taste lemon/chili instead. Don't overdo it or your dogs might avoid their water and food bowl because of the smell.
- Lay pieces of adhesive tape around the edge of the counter, sticky side up. When your dog puts his paw up there, he'll notice the tape sticking to it. Most pets (works well with cats, too) are either scared or annoyed by the tape and run off. Be aware that you need to be able to remove the tape from the fur. Use something like painters tape, which releases easily and don't even think about using duct tape!
- Tie several small empty soda bottles or cans together with a long string. Leave a few inches between each can and a bigger gap right in the middle. Tie some food to the center of the string and set it all up in a long line on the counter, then leave the room. When your dog tries to steal the food, he should be scared by the rattling cans. Immediately return to the room, take the food away but don't interact with your dog otherwise.
- There are several commercial products available that sound an alarm if anything touches it (alarm mats) or moves in front of it. Google for "pet counter alarm" if you're interested.
To make it absolutely clear: You won't reach your goal by going for the alarms / countermeasures first and ignoring the training and putting things out of reach. Dogs are natural scavengers. Leaving food around is an open invitation to take it. Even if only 1 attempt out of 20 is successful, your dog still knows that your counter is a possible food source.