For those who enjoy tinkering with data, the Wall Street Journal has created an interactive chart using the MTA's numbers on the city's MetroCard usage by the areas closest to subway stops. You can compare whether people use 30-day unlimited cards, pay per-rides or senior discount cards, and look at which type of fare increased or decreased after December's fare hike (data on student card usage was released too late for the chart). Then look at the demographic data in the neighborhoods of each stop and generalize away!
For instance, the WSJ writes, "30-day unlimited cards are particularly popular in neighborhoods with large Asian populations," where they sometimes represent 50% of all MetroCard swipes in areas like Canal Street in Manhattan and Sunset Park in Brooklyn. And at the Bedford L stop in Williamsburg, less than 1% of riders use a senior-discount card, which probably includes the members of Sonic Youth.