Indian Dancing & Prostitution
I've heard that this sort of Indian dancing was once looked upon as a form of prostitution or a way for prostitutes to entice their audience.
This was true in some areas of India when courtesans went out to earn their livlihood, they would turn to dancing to entice their customers.
Just as massage as a profession is well known, there are the non professionals who have used it with impunity and it is known/regarded as a synonym for prostitution in some quarters.
Like in all endeavours, look for the certiifcate of authenticity (school leaving papers, certificates, etc to find the true art.