These aren't cam girls or people out to make money.
These are real exhibitionists who love to be watched while they have sex.
Phone sex, as a part of the overall adult industry, employs less than a few thousand persons, this includes the web cam hosts who answer phone while performing on camera for customers.
There are many free chat destinations online that are 100% free, but many of those require you to register and give up your email address in order to use them.
Most of use do not want any more spam, and so we are reluctant to give up our email address, especially to adult or porn companies.
Some of the free adult chat services require a credit card, even though they claim it is only for age verification, and you will not be charged, sometimes "during free trial" in small print.
There are some good, totally free chat services that do not require a signup or email address for verification however.
There are however a few great places on the web where you can chat away without signing up, without registering, and without giving away your email address or credit card information.