I don't know of a lot of folk tunes used in Australian tv ads. I can't think of any at present.

Not folk, but there must be an ad-man (or woman) in Australia who loves Ian Dury's music, because there is currently an ad for Woolworths using "I Want to be Straight" (odd choice) and there is an ad which pops up now and then for a cleaning product, using Billericay Dickie.

That one bothered me for years because I knew the tune and couldn't place it, and couldn't watch it until someone told me that was the tune. I didn't have that album then, so had only heard the album a few times.

[Off topic: a couple of decades ago our local regional tv station had a tune they played at ad breaks in movies. It cracked me up, because it was a fun, jazzy tune, but it was Frank Zappa's "I am the slime from the video, oozing along on your living room floor". How appropriate!

It was abruptly changed, and I expect that someone was severely reprimanded for that.]

Helen