The symbols have got the power pins 'attached' to VCC and GND.
If you want something else you have to edit the symbols, especially those pins and set them to visible.
EEschema seems to create global labels on the fly for pins that are invisible in symbols, so they get connected when you create the appropriate connection 'somewhere' in the schematic.
I'm pretty sure the beginners tutorial will have covered that one..
This will make it easier to concentrate on the function of the IC in question, without the need to wire power to each and every one of them - less clutter.
Personally I don't use the kicad libs, so I have no real experience with this feature and the schematics I work on are not that complicated that I would need 'less' clutter .. yet.