Question about Tiptronic

I just got my car a couple days ago and have never owned a tiptronic transmission before.

When I am driving it in manual mode, if I push the buttons on the steering wheel it will automatically go into standard mode without me needing to touch the shifter. Is this normal and how it is suppose to work? What is the point of having the control on the shifter as well if it can be activated by the steering wheel controls? I actually find it a little annoying since I accidentally pushed the button on the steering wheel while driving and it went into standard mode unexpectedly.