Yes.
I'm think unpaid work experience and unpaid internship positions can be worthwhile.
Many people spend thousands of pounds on work experience placements in the fashion, legal or tech industries.
The experience, skills and professional contacts acquired can be very valuable.
But many business do sail perilously close to illegal conduct- luring applicants for work experience/internships with false claims of potential employment for their own financial benefit, using them as an off payroll free workforce and not providing promised references.
I've done plenty of unpaid work experience without expenses; to obtain practical experience, knowledge of the sector and for the potential to make contacts. Similar approach towards charity volunteering for vital causes, although all of those did offer some expenses to those volunteers willing to accept.
Some work experience/internship managers & staff were nasty, demanding and gave the impression that they view it as their personal mission in life to victimize the 'free labour'.
I know a few horrid bullies at the Trussell Trust who indulge in similar behaviour.
But that's life, those were an unpleasant few that tended to alternate between trying to butter up those with senior roles above them they considered worth their while and abusing everyone else.