I decided to go to a BC game at the last minute years ago. Didn't plan anything...had no ticket, didn't know where to park or anything. Got off I90 near Chestnut Hill, saw a park for BC football parking, followed the signage and ended up in an office park in the middle of nowhere.
Lots of green space and parking. People were tailgating.
They had old school yellow school buses to shuttle fans to the campus. Cost to park was not bad. Maybe $20.
Not sure where the office park was but it I remember we went through some really nice neighborhoods going from there to the campus.
It was the Diamond Ferri game. The ride back on the bus was fun. BC fans kept saying they were still going to the Fiesta Bowl. I told them they were out. Some cried. Not as much as the ones wearing sombreros to the game though...
Anyway, that might be an option. But looking at the BC web site for parking, it might not be an option anymore. I guess it was too convenient.