... I'm involved in a new Delaware corporation that was just registered....
That doesn't give you any trademark rights at all.
TM's come from use, and you can't even show that - let alone a registered mark.
Your example of the brick/mortar ice cream business is a different story, slightly... but it is also completely irrelevant to the scenario you've described here.
Was it a skeezy thing that somebody did? Definitely.
Is that criminal or even something you could take legal action over? Not likely.
Was it completely stupid for you not to have spent the $9 first and registered the name in this day and age? Yup.
Now... what you really need to do is find out who has the domain. Then, instead of bull rushing them in an aggrieved manner screaming "entitlement, criminal, etc.", you need to calmly find out what they want for it. Bet you its cheaper than any "legal action" you could attempt and it guarantees you'll get the name - whereas the legal route does not. But take the approach that "you are entitled, they are scum, you'll take action" and you'll find them far less cooperative and expensive... speaking of "expensive"... do you have a clue what it might cost to TRY to take the name through the legal channels?
Just something to think about.
Again, I'm not condoning the current Registrant's behavior at all, that IS a scummy thing to do. But you'll get much further disregarding that attitude when dealing with them to get the name (that you SHOULD have already registered) for the least cost and aggravation if you play "nice".