Let the boss of the house sit next to you on the couch, the cat. LMAO yes my cat begs too, but she at least does it politely and has learned that sneaky paws get her pushed off the couch. As for Tiggy, and Reggie begging she has taught them to back off away from the couch, she's such a hag sometimes but it can be funny. So if they get to close she swats them and/or hisses. Sometimes she even jumps to the coffee table and pushes them farther away.
I know sitting at the couch to eat helps in NO WAY to improve begging, but we are lazy, and Tiggy has just recently started to test the boundaries again, he's in the phase. So thats why I thought of it and I noticed tonight the part if Pigmy is on the couch with us, he avoids the couch.