Occasionally you’re confronted with evidence that people knew what was up long before plastic bag bans and Priuses were all the rage. Like today, when my own mother stopped by with a cloth tote bag she’s been using since the late ’70s. Ironically enough, the bag bears the logo of Encore Books, an East Coast chain bookseller that went bankrupt a decade ago — so the stores are gone but the bag’s still in terrific shape. Mom was amused by the flurry of photo-taking that followed. (Pics came out too dark, unfortunately.) “It shrank when I washed it,” she told me. “But it works fine.”