Case in point, Olympiakos just tied 0:0 as a -1000 fav despite 9 shots on target and 13+ corners.
Meanwhile a +600 dog Genoa is winning 3:0 at HT after 3 shots on target. I see it all the time, teams at plus odds somehow have no problems scoring multiple goals. I often feel very confident taking a side at +150(and they win 3:0) but when I am to take a -200 fav I always fear a draw.