I had one case of known beetle activity after they arrived in my humidor from CCs (several from NCs but in the long distant past). When you catch the little bugger in the act, it's a big hint.
If I am buying cigars that are not more than 2 years old (an arbitrary number), then I freeze. Old stock I do not freeze because I worry about potential wrapper damage and figure if they haven't eaten these sticks yet ...
My humidors get to 80* and sometimes above during the summer. I've not had a breakout in years and never from a box that I froze.
Knowing my luck, guess what I'll find when I get back from vacation