I've been an agent - theatrical rather than 'sports', but the principle is the same. It was my job to seek opportunities (auditions, castings etc) for my Clients (actors) that might lead to jobs for them. I didn't get paid a single penny unless the Client 'landed' a role and then I would get a percentage of whatever they got. The percentage ranged from 10% to 20%, depending on the type of job, but as pay in the entertainment industry is a pittance (unless you are Helen Mirren or Anthony Hopkins) I wasn't exactly 'rolling in it'. If I made 10K in a year that was a good year! Being an agent was pretty much a thankless task. The Client would always blame you if they didn't get the right sort of opportunities and expected you to work day and night (for nothing, most of the time!) Everyone else thought you were, how did justanotherfan put it? Oh, yes, 'a money grabbing shyster'. I wasn't - but I can't speak for the guys and girls that represent footballers.