If it's good enough for celebrities to do it then why shouldn't I do it ? Well, you just shouldn't do it.
Apart from being a no no with health authorities, it's also a bad habit and the dog might jump on the table at home when you're not watching. I guess you would be aware of that at the time when you decide to feed your dog from the table.
These days people don't take responsibility for their actions be they thoughtless selfish or just silly. I'm sure you're not that sort of person.