line jockey
n: generally, the guy (husband, boyfriend, younger brother, etc) who gets dragged to the mall the days after Thanksgiving and Christmas. Their sole purpose is to hold their wife, girlfriend, sister, etc's place in line while they shop. They can be sighted as looking extremely sad, bored, and tired. If not in line, they are forced to hold the bags. In some cases, they have to stand in line while waiting for the other people, but the people don't show up before they get to the front of the line, and the line jockey has to go to the end of the line and wait again.
For as long as he could remember, Little Johnny had been a line jockey for his Mom and sister.

The unhappiest person in a department store is a line jockey.