The answer comes from the man best qualified to answer that, Jesse Owens himself.
"When I passed the Chancellor he arose, waved his hand at me, and I waved back at him. I think the writers showed bad taste in criticising the man of the hour in Germany."This quote can be found in his 1970 autobiography, The Jesse Owens Story. So who, if anybody, 'snubbed' Jesse Owens? Once again, the man speaks for himself:
"Hitler didn't snub me, it was FDR who snubbed me. The president didn't even send me a telegram."
Roosevelt did not want to be seen shaking the hand of a black man when such a gesture might have cost him valuable votes in the southern states.
The Jesse Owens story.