Sometimes you have no choice, when we went to Fenway, we were coming down from RI, so we had to park. We did find a service lot 2 few blocks away, but there is no real parking at either stadium.
To me both stadiums are like Kinnick in IC, if you are a fan of the team, its a great stadium, but for the other team or the causal fan, its an old relic that would be better off replaced or modernized. Both the Sox and Cubs have down a decent job modernizing both stadiums, but there is only so much you can do, and they both have a small footprint to work with.