Are unpaid work experience internships ever justified?

@londonmyst What are these three jobs you do and don't get paid for?

I think you may have misunderstood my previous posts, either on this thread or on other threads.
I am working three jobs that I do get paid for.
I volunteer with a charity to support honour abuse survivors, another charity helping rape victims and help out independent authors & academic writers with proofreading, copy-editing and reviews.

Thanks. Earlier in this thread you said you were "living off under £30 per week".

What's your overall goal with doing those roles?

I have to work to pay my rent, minimum credit card payments and living expenses.
Volunteering is to help some of the people who most need it and whose only viable means of support is being delivered by volunteers/charities.

Really I'm asking why are you pursuing with proofreading and copy-editing? As far as I'm aware that's become a terrible gig because of how easy it is for people to compete with one another on sites like People Per Hour. I'm not trying to sound like a **** either. I used to write freelance copy for businesses; I also worked as an audio typist. Both roles become unfeasible in the long term because of how stupidly competitive the market is.

Props on volunteering

I'm not trying to make a career out copy-editing or proofreading.
I just do it to help out independent writers and academics, who don't have access to the budgets or support networks available to authors with big five publishers.
Although one author I helped out did recommend me to her new publisher for a part time job.
That opened up sponsorship opportunities and helped expand my contacts.