The company I work for issues laptops to staff as standard. They all have to have a standard company build (there is more than one build, depending on need) and all have whole-disk encryption.
I have been a laptop user since 2003. The company operates from a number of sites in the UK and even more worldwide, and the need to work from a different office to one's 'home' office often arises. In addition, the company provides good infrastructure to facilitate home working, with the security aspects that come with that being robustly addressed.
I like being able to take the laptop with me when I leave work, knowing that the next day's work may be at home or in a different office. A lot of work is done on servers that are located in datacentres, and these are normally accessed via Remote Desktop. Actually having to visit a datacentre is quite unusual, with a number of security and prior notification hurdles to overcome in order to do so.
Early laptops did not perform as well as desktops, but the difference for the most part is not significant nowadays. And if the power goes out in the office (or wherever you are), you don't lose your work as the laptop battery will keep it going until you can save it.