According to this blog, Mosquitto (the MQTT broker) now supports connecting to clients over web sockets. The blog article seems to hint that web sockets are more useful for browser applications, since web browsers don't support proper TCP sockets (yet), although the web socket protocol is supported by the majority of modern browsers.
If I just have various clients in a network (e.g. sensors and actuators based on microcontrollers such as Raspberry Pis), will there be any advantage to using web sockets over direct TCP connections? Is the overhead of the web socket protocol only worth it when you are communicating with a browser?