I first heard this around 1974 on a Firesign Theater record, Lennon and Marx, in the skit Nick Danger, Third Eye. It went "What's all this breww ha ha?" Nick anawered "brew ha ha?" Then they went into laughter with ha ha ha.
I then heard it said regarding how Starbucks Coffee was causing a stir in the media by using quotations on their coffee cups. Brew ha ha was a clever play on words.