The performers advertised the opening of new stores and other venues, or promoted special events such as price discounts. Nowadays, chindon'yas are rare in Japan.
The word consists of Japanese sound symbolism chin and don to describe the instruments, and the -ya suffix which roughly equates to the English "-er" suffix in this context.
They are so friendly, and willingly accepted to be taken a camera.
When we took a camera, A passing Osakan Obachan joined us without our permission. That's Osaka no obachan (midle aged outspoken housewife women).