It doesn’t matter how many subscribers these newspapers are reaching. The surprising fact in the stimulus is limited the people who actually are subscribers, no matter how small the number.

These newspapers would fall into the “not covering election issues” category. We need to know why people who subscribe to newspapers that do cover election issues aren’t better-informed.

Rather than reading the election coverage, these subscribers just do the crossword. This explains why they’re no better informed than the other subscribers: because they don’t even read the coverage that these newspapers offer.

This exceeds the scope of the stimulus. We care about people who do subscribe to newspapers, so facts about people who don't subscribe to newspapers are irrelevant.

We don’t care where most voters get their information from. We care about the ones who subscribe to newspapers, and this doesn't tell us anything new about subscribers.