The Reading striker has taken the stance as he believe the anti-discrimination body has failed to tackle racism. However, Ferguson believes Roberts is misguided.
"I have to disagree with Jason Roberts. I think he is making the wrong point," the Scot said. "Everyone should be united, with all the players in the country wearing the Kick it Out warm-up tops."
Ferguson added: "I don't know what point he is trying to make. I don't know if he is trying to put himself on a different pedestal from everyone. But he really should be supporting all the rest of the players who are doing it."
Roberts does not feel Kick It Out have been strident enough in their response to the John Terry and Luis Suarez racial abuse incidents. He told BBC Sport on Thursday: "I find it hard to wear a T-shirt after what has happened in the last year. I won't wear one.
"I'm totally committed to kicking racism out of football but when there's a movement I feel represents the issue in the way that speaks for me and my colleagues, then I will happily support it. I think people feel let down by what used to be called 'Let's Kick Racism Out of Football'. People don't feel like they have been strong enough."
It has been suggested other players will follow Roberts' lead. As a leading anti-racism campaigner, United defender Rio Ferdinand - whose brother Anton was the subject of racist abuse from Terry - would be an obvious candidate.
However, it does not appear that will happen. Ferguson added: "When you do something, and everyone believes in it, you should all do it together. There shouldn't be sheep wandering off.
"I think he is making the wrong message.
"All the players are wearing it. I have only heard that Jason Roberts is different - but he is very different. He plays a game and is in the studio 20 minutes after it. That is a great privilege."
Source: PA
Source: PA