My aunt is a travel agent and I don't think it was any cheaper going through her. However, I have often been with her at her beach house on weekends when (usually right before we are going to leave for the beach) she has received a phone call that a client has broken their leg skiing in Japan, etc. and she has had to and has been able to get them home ASAP. One of her clients was even on the news a couple of months ago when flights from Bali were cancelled due to an ash cloud and one of her employees was able to get the client home via Thailand (unfortunately they cut the agency's name out of the report though!). So no, there's no real advantage to using a travel agent, but it is helpful if something goes wrong. It's therefore up to you to decide how difficult and how necessary it would be for you to get home - if you're not in a foreign country, in a place where there are frequent flights home, etc. then I don't know that I would bother.