ATMega328 Fuse Bits & Boot Loader Wiped

I have some atmega328 chips and the fuse bits have been wiped (not by me) along with the bootloader. Any ideas as to what could cause this?

P.S. I already CAN fix the issue I'm just curious as to what is causing it. I do NOT want fixes for the chip itself, just suggestions on what could be causing the issue.

Didn't think that was possible without reprogramming via ICSP, or via "high voltage" programming.

Assuming I was using a 5V regulator and a 12V wall wart, could an accidental HV programming take place?

No.

I wonder what took place then. They can’t just randomly drop the boot loader and reset all fuses to 0x00.

How can you tell all the fuses are at 0x00? What are you using to show that?