Over in nearby Needham, both the RI and Sheraton charge for parking too! (Although the Sheraton waives it for Plats and above.). Which is equally ridiculous, and the Homewood Suites Needham in the same office park complex does not charge for parking.
I'm surprised to hear the RI charges, they definitely didn't have any gates when I was there last summer. We used the lot for outdoor meetups during Covid Lockdown as it was equal distance for a group of us to meet outside and under cover, if needed.
That Sheraton has had issues with theft from vehicles for many years. Do they have separate parking for the restaurant not behind the gates? (and folks in Newton consider the Needham Industrial Park, where those two hotels are, to be "miles away")