The French striker, who has made just one Premier League appearance for the Baggies this term, is attracting curiosity from some clubs in England's second tier and Appleton feels it is warranted.
"You'd be disappointed if there weren't clubs, Championship clubs especially, interested in some of the players that aren't getting in the team at the moment," he told the Birmingham Mail.
"Marco's found himself in a position where he's not been in the squad in the last couple of games. Even when he has come back in he has not got back on the field yet.
"I wouldn't be surprised if there is interest from other clubs in him and people like Roman Bednar, who have decent records at that level of football."