The linked-away Celtic hitman was substituted on the hour mark for Leigh Griffiths.
The Frenchman slowly left the field of play with a sluggish demeanour and many Hoops fans on Twitter believe that his body language indicates that it was his last game for the club.
And former Rangers striker Thompson says that Dembele - the subject of an £18 million bid by Brighton & Hove Albion on Christmas day - was an 'embarrassment' for the way he exited after his "shocker" of a performance.
He told BBC Radio Scotland: "I thought it was embarrassing the way he came off the pitch. It was embarrassing, embarrassing!"
"He'd had a shocker. Just get off the pitch and get your sub on. I thought it was terrible from him."
Celtic will not play another game until the Scottish Cup visit of Brechin on January 20 due to the winter break and it's not unthinkable to believe that Dembele might well be gone by then.
The former Fulham hitman has been below his best this season and has only managed to score eight goals in all competitions, having scored 30 last season.