I've heard that my whole life in the US. I think my dad taught it to me when I was really young, because he loves cats and our neighbors across the street had some outdoor cats.

We do it in Italy too, afair (I'm a bit in doubt if we also do "tch tch tch")

It’s very common in the USA.

Can confirm that non-greek Americans do this as well.

No, it's somewhat common here in Brazil too.

And Romanians.

My German grandmother did it, too.