fake-lifter
1. (noun) A person who pretends to display physical excertion amongst a group that is carrying a large heavy object, where in reality that person is not contributing to the collective strength at all.
1. Nobody passed Smitty a beer after we moved the piano because everyone knew he was just a fake-lifter.
Fake couch lifter
A person when asked by a friend or associate to provide assistance with some task, agrees to help, shows up and then fakes his assistance by utilizing deception with the expectation of garnering thanks but providing no actual effort towards the task in hand.
Fred, the Fake Couch Lifter, showed up the other day to help us move house. When it came to moving the couch, he reached under the couch but did not exert any energy, thus giving an erroneous impression that he was helping to lift the couch