The Federal Reserve is suggesting it could still hike interest rates in September, but it may just be trying to manage market risk in doing so, Barclays chief U.S. economist Michael Gapen said Friday.

"The rate hike soon is the Fed's equivalent of free beer tomorrow. You come back into the bar the next day and it's still free beer tomorrow," he told CNBC's "Squawk Box." "So it feeds the perception that the Fed really doesn't have a desire to move rates any time soon. They just don't want markets to get too far away from it, lest financial stability concerns rise."