Conor McGregor's already puttin' that UFC 229 money to good use ... 'cause he just surprised 10 Boston firefighters with World Series tickets!!
We're told McGregor wanted to do something special to show his appreciation for the firefighters ... so he plunked down a good chunk of change for 10 tickets to W.S. Game 1.
Remember, Conor says he made around $50 million from the Khabib fight -- and around $100 mil for the Mayweather fight -- so it's nice to see him spreading the wealth around.
McGregor personally delivered the goods to the Back Bay Fire Station .