They nominally charge $35 booking fee which is potentially offset by the gift cards they offer for the booking done through their website. As of this writing their are offering a minimum of $200 in gift cards for the "flight + hotel" package regardless of price booked through them and also waiving $35 booking fee if you use some of their launch partner promotion code (google it and you will find few of them easily and you can enter them here). Although their primary target audience is business travelers you could still book the trip through them for leisure and earn the gift cards. So potentially it can be very lucrative offer to give them a try if you are looking for a weekend outing somewhere close by where you can essentially earn $200 in gift cards easily.
Their package cost are usually equal or less than the cost of flights and hotels if booked separately but at the same time providing you with good value gift cards. The biggest return is if you book international itineraries but even domestic itinerary would give you good value for your money. Also you do have option of making your trip "refundable" but at a higher cost. Below is one of the examples of available trips which looks very attractive using their promotion.
So, take upside for a ride and see what you can find for your getaway.