Yes, a thousand times yes!
Google searches are the single largest source of sales on Bandcamp (surpassing even Facebook), and your fans aren’t just searching for the name of your band, or your latest track — they’re frequently searching for that one lyric snippet they remember.
If you haven’t added lyrics on Bandcamp, those fans are likely ending up on lyriczzzbay.com instead, which is showing them ads for Applebee’s. Why should some other site get first crack at engaging, and ultimately, profiting from, your fans?
Don’t let that happen. Add lyrics.
Also nifty: when you add lyrics to a Bandcamp track, we embed them in the download. This means that, on the iPhone, for example, fans can tap the screen to view your lyrics overlaid on the cover art.