Why does my project from Tp_TopDown template reference Tp_TopDown classes?


I just started with UE4 and I would like to understand the basics before progressing.

I created my project from TopDown C++ template. However I found some lines in DefaultEngine.ini file


However, I cannot see where are any of Tp_TopDown classes referenced in my project. I see that MyGameMode is set in project preferences, it points out to MyCharacter Blueprint and other My* classes. However when I remove those 3 lines from .ini file project does not work correctly, because of MyCharacter Blueprint.
However, when I open this file in Editor I see no references to any of Tp_* classes, only to MyProjectCharacter as a parent class. But when I open this MyCharacter blueprint file in text editor I see some mentions of Tp_ classes.

I would like to ask why’s that - why we need to substitute some classes in such a dirty way (by some magic .ini file), why Blueprint editor does not show me references to TP_ classes, why templates works this way and why my project from template was generated this way.