Random Amazon Recommendation

You know the "if you liked x, you'll enjoy y" recommendations that Amazon likes to make. Occasionally, it is spot on but tonight I received a suggestion of

Beyond the Square Crochet Motifs

Recommended because you purchased Boston Red Sox 101 (101 My First Team-Board-Books) for nephew Xavy!

Is that a not truly random combination? While it is true that I like the Red Sox and I like crocheting, it is probably 20 years since I picked up a crochet hook - before Amazon even existed! Does this mean they have a webcam trained on my sewing basket (which does indeed contain a crochet hook or two)? Do they know me better than I know myself? Should I be crocheting while I watch the Sox beat up on the Yankees? (I hesitate to type that sentence lest I jinx the rest of the series!)