Everything Billdeshivs said is certainly true in the context of "it's possible".
I don't think I have ever dry fired a shotgun for practice and I am big on dryfiring pistols and rifles. I would not begin to worry about damaging a Maverick 88 by dry-firing though.
https://en.wikipedia.org/wiki/Work_hardening
I have some experience with inconel and other alloys work hardening. I have heard of black smiths hammers shattering after work hardening. I have not heard any reports of it in anything close to the impact of a light spring propelled firing pin's shoulder against the end of he channel. I'm not an expert and I would be surprised if it occurred, but work hardening can be as odd as chatter, so it is certainly possible.