What started people to say blah blah blah?

[Maria Arias]

Just wondering. And im bored.

[ace]

i think it was questions like this one that got it started blah,blah,blah.

[Ray Alvarez]

Idk, but i still prefer-yada,yada,yada..bored 2.

[Literally]

well i assume the etymology of the phrase blah blah blah originates from the word 'blah' meaning bland or dull.

[Mark]

impoliteness,when someone informed me of this i ceased to say blah blah blah

[adry]

Presidents

[The Canuck]

Kesha caused it.

[gil m]

People who were bored with blah blah blah changed it to yadi yadi yada or other such nonsense.
Some will say and so on and so forth, but try to take it in stride, etc., etc., etc...