I think there's a big market for noise or acoustic masking instead.
I do not enjoy the TV Mobile public speakers on SBS buses, and my headphones will not mask it out totally. Instead many young teenagers turn up the earphone volume too loud against the environment noise, so that even strangers standing around can hear it.
These days there are so many constructions and upgrading works creating noise.
And people can't stop talking too. You will be very lucky if you find a good listener friend, there is only 1 in all the friends I have.
Aircon Foodcourts are noisy too. Air-coned buildings and indoor environments constrain all the noise within.
The urban society is sooooo NOISY.
We have got so used to noisy environment, that when we need to search for internal peace or yoga, we need to listen to some Nirvana or relaxing music from external.
Then when we use some instruments to hear ourselves, seems many cannot hear properly. And I have heard some people asking if lizards make any sound, and thought they are quiet.