Massacring the language

I've been binge-watching Mad Men to catch up on the seasons I missed.

While watching, most of my brain is naturally occupied in thinking:
"Geez, these people drink, smoke, and have sex a lot."
"How sexist is THAT???"
and
"Why can't I look like Christina Hendricks?"

But in spite of that, a teeny part of my Wordlady brain was still functioning enough to think "Well, that's an odd pronunciation!!" on hearing one of the minor characters pronouncing "massacre" as "massacree". I even rewound it to make sure I had heard aright. 

Once I got over my "Don't young actors today know how to pronounce words properly??" reaction, I thought I'd better check it out.

Turns out the OED has this to say about "massacree" (for which they have written evidence going back to the 16th century):

it is reported ... to have been widespread in England from Northumberland to Somerset in the 19th cent.; it is recorded in a few 20th-cent. regional glossaries. In the Dictionary of American Regional English it is reported to be chiefly U.S. Southern and South Midland, and old-fashioned.

The actress in question, however, (David Mamet's daughter Zosia Mamet) was born in Vermont, grew up in California, and is not yet thirty. I wonder where she got this pronunciation from and whether it caused any reaction on the set (if it did, she was obviously not asked to "correct" it). 

On the other hand, it might have been an intentional channelling of the famous Arlo Guthrie sixties protest song "Alice's Restaurant Massacree". Where Guthrie got the pronunciation from I don't know, because he was born in New York and was referring to Massachusetts.

Have you ever heard "massacree"?