Gibson Lifestyle has a great read about Billie Joe Armstrong's love for acoustic performances. It details how the band always used to bring an acoustic guitar on tour "in the early days" as he describes it. There are a few videos to demonstrate the power of the sound, and of course, among them is "Good Riddance (Time of your Life):"

But real superstardom was still around the corner, and after a short re-grouping and rest period, their 1997 album Nimrod brought a new dynamic, the chiming ring of Billie Joe's acoustic guitar on "Good Riddance (Time of Your Life)."

'I was trying to make the acoustic guitar sound like a percussive instrument, the way Pete Townshend does,' Armstrong explained.

Gibson makes a valid point how acoustic can "turn a good song into a great song." You can check out the mentioned article in the link above.