Expedia IS a travel agent.  They are an unseen dot-com travel agent.  The have no office in your locality and you are not working with a real live person.

As to compensation:  Disney pays the dot-com and the travel agent.  Both the travel agent and the dot-com may or may not charge you a nominal booking fee.  Did you know you pay a booking fee if you call an airline for a reservation?  And you only get THAT airlines information not all the airlines information. 

You may be surprised at the value added a REAL travel agent can give you.