Internet connection is required - why?

I've run over 2 floors at. On the ground floor the Cube, on the 1st floor thermostats. I am very pleased with these devices. The instruction manual is printed way too small and incomplete. In the operating instructions reference is made to further information in an Internet guide. for example. when it comes to battery change / reset / restart of a thermostat.
Internet is well condition.
A shame really wonder what my data have to search the Internet if I do not want to use the remote control via Internet.
The remote control via radio in the house works as I said smoothly.