As someone who unfortunately worked for a ringtone vendor for a shot period, the main thrust of the "industry" was mis-selling a hidden/deceptive "subscription" service to children, which was billed through automatic premium rate mobile phone charges. It was a con-job where phone companies and shady ringtone companies conspired tp rip off children who were too embarrassed to tell their parents they screwed up by unknowingly entering into the subscription (by texting something to some number), and couldn't work out how to cancel the subscription (because this was made insanely hard). And then the next month they would get charged again.
These people were scum.
also - they never paid the music publishers, as the purchaser/subscriber obtained the ringtone they purchased/subscribed for, but rarely "cashed in" the subscription "credits" for additional ringtones, and the music publishers were only paid for ringtones actually downloaded ... so it was also a con on the music industry.