Many of us do have careers in addition to our professional companionship services
Sure.... there are some that do it because they have no career options, and have not found their niche in life.. but there an awful lot of us out there that do it because:
A) We can.

B) We enjoy it - the attention/compliments, the money, the wonderful (for the most part) gentlemen we meet

C) Freedom - not having to work full time, setting our own schedule

D) Some of us are single.. like to mingle.. have needs too, but do not want relationships at this point in our lives.
I myself have been in and out for years, and always come back to being a courtesan. I do consider Professional Companionship to be a career.. one I have come to love, and have really perfected my skills and level of service.
I also love my other career - and own a small business in that field.
There are some that have a need to please, and feel desirable.
Whatever the reason... many are able to get "regular" work, and have it - or choose not to.
I believe that far too many people spend their lives working. Full time work and over time are not for me. I prefer not to be exhausted at the end of the week from work.
Lazy I am not - but I am all for quality of life. Professional Companionship enables me to have that.
I am also enabled to further my small business, go on vacation abroad, eat all the expensive organic foods I want, take as many educational courses/workshops as I have time for.
I do, btw, come from a middle class family

Oh - and my parents are still married... a million years later (no broken home). I have never been sexually abused, nor had a drug problem. Oh - and my parents are still married... a million years later.
I am independant, and have never been coerced into this line of work.
Like many others here, I break the stereotypes that society has.