Unless the shell is launched as a "login shell", which is the system's way of signaling to the shell that this is the first time the user is interacting with the computer for this session, it is started as a "child" shell.
"Login" shells source the environment from whatever control mechanism is set up (/etc/profile, /etc/profile.d/, and usually local dotfiles like .profile and .bashrc (if bash)).
"Child" shells just inherit their parent's environment, but sometimes also run some dotfiles depending on how they are configured.
In most systems with X configured, the dot files are sourced by whatever process starts the window manager and xterms or konsoles or whatever just inherit from that. This is because it isn't considered a login session, since you were already logged in when you started the konsole.
You can set your konsole to run 'bash --login' if you want, but this might have unexpected side-effects later on when you run something which depends on an environment variable that you are clobbering with the --login parameter.