The concept of "Software-as-a-service" is the direction that most significant providers are going in several industries. It means that your provider runs your IT operations for you - avoiding your costs and resources to keep your equipment, systems and data operational. The average down-time for a server on-site in a hotel or resort is significantly higher than that of both your average internet service provider and servers (like ours) hosted in a secure facility with redundant power and direct, triplicate back-bone access for internet. So from an operations perspective, there are a lot of arguments for having your software and systems run for you.
From a deployment and training point of view, the ease of being able to use just about any computer (or mobile device) and simply turn your browser on and you have secure access to your data and system is also very useful. Because the application is browser-based, it also (normally) means that training is easier as the interface is something that most people are used to.
Finally, in terms of the data - you are free to take regular back-ups of any of the data. We could arrange for a backup copy to be sent to your on a schedule if you wished. The data is YOURs, though. We are simply managing it with the whole system for you. Just like with any piece of software you run, you use it as you wish and need, but it is provided as a service as it is from us, we give you the added bonus of knowing that someone is always on watch to make sure that you AND your customers have a working system with secure data.