If I come to your house, destroy your door, steal your mom's dinner for 4 ppl, are we both cheating?
How about we compare with something actually worth comparing for? For example switching channels when there's the ad break, or turning the sound off, etc.
When I download something, I'm not "stealing it". When I block an ad, I'm not stealing either. I didn't remove 10$ from Google's bank account that was there before.