If "these caching(sic) processes" is referring to Akonadi services, then you are most likely unknowingly running "or any other software that they support."
Akonadi is neither autostarted nor restored by a session manager (unless one manually adds autostart support files, which is highly unlikely in your case), but started on-demand by first client.
I think there is a list of less known clients on userbase.kde.org which are known to cause Akonadi startup for users who are strictly against PIM data integration features.