Jamie Jungers is starring in an ad, Ashley Dupré is promoting the New York Post—even Monica shilled for Jenny Craig.
She never wowed the nation with her athletic prowess, shilled in countless car commercials, or entertained in film comedies.
"one who acts as a decoy for a gambler, auctioneer, etc.," 1916, probably originally circus or carnival argot, probably a shortened form of shillaber (1913) with the same meaning, origin unknown. The verb is attested from 1914. Related: Shilled; shilling.
: That summer he shilled for a sidewalk hawker (1914+)
[origin unknown; perhaps, since it is a shortening of shillaber, ultimately fr Shillibeer, the name of an early 1800s British owner of a large bus company, the reference being to persons hired as decoys to sit in buses and attract passengers]