Because if there is money involved there is incentive to do it for a living, which leads to incentive to cut costs and that might not always be done in a consum

Because if there is money involved there is incentive to do it for a living, which leads to incentive to cut costs and that might not always be done in a consumer-friendly way; therefore regulation is needed. If there is no money involved, the people who would cut costs and make it unsafe for the consumer are rarer -- since they can't do it for a living, and the relationship is harder to regulate since the only thing involved is communication between two parties, so it's probably not worth it.