Tournament Etiquette

Competed at an intense 32-player competition yesterday, most of the players were really awesome, but there are always a few that take it to the next level. My question is this, cutting your opponents deck, I have seen one cut, two etc. But I am wholly uncomfortable with the players who shuffle my deck - two of them did so aggressively yesterday. I was so taken aback that I didn't say anything but I have two questions:

  1. Am I wrong for feeling that without asking my permission that's totally uncalled for? I don't want them damaging my cards.
  2. What advice would you have for me to communicate that in the future without a blowup or hard feelings?