Short periods of informal work-experience and properly developed internships have for many years been a feature of the labor market, and are a benefit to young people and near-graduates transitioning from education to the workforce.
The intersection of volunteerism, work experience and employment is a minefield that is not space alone for industrial academics to have a view on. The broader community needs to be involved, as do education institutions that encourage students towards summer and holiday internships.
Care should be taken not to vilify internships as a whole, or turn employers away from offering them. We have to be mature enough to learn past lessons that severe damage is done to honest and fair-minded businesses and staff by over-regulating at the lowest common denominator simply because a handful of examples of abuse can be found. Regulate the abuse, not the concept would be the right approach.
It is not unusual for family, friends and associates who are studying to undertake unpaid work-experience in businesses and offices across semester breaks and holidays, perhaps even politicians' offices. Provided they are not exploitative, the net benefit of those arrangements is also well established.