That's the way every Debian based distro does it! All packages are download first on any upgrade, during installation some may ask questions when altering config files. A reboot is performed to ensure all the new packages are now being run
You can get away without rebooting after minor upgrades, but you will have to restart anything application or service that has been upgraded, as otherwise the old versions will carry on running.
I don't recall Wheezy, Jessie and Stretch doing anything different than the above!
---druck