The on-line travel agencies made up of companies like Expedia, Bookingdotcom, Priceline Group, TripAdvisor, airB&B and increasingly, Ctrip et al, have been trying to corner the market and have done a really good job of selling the idea that they give the best deals.
A new movement 
, Book Direct, has been set up lead by global players like Hilton, Ritz and Marriott chains as well as many small independent business to explain that booking direct is the cheapest way to book your stay.
At the Old Manse, Kilmartin we tend not to use these agencies, having people booking direct via our website, thus keeping the prices down for our customers and ourselves.
What to know more about book direct read this report Direct Booking versus Using Online Agents? A Survey Among Hotel Users and Hoteliers