A nonprofit organisation organized a big event, which included the possibility for the participating guests to sleep in (empty) barracks for a small fee. The organization looked for volunteers to keep a night watch there, which was required for safety and access control. Several volunteers agreed to take shifts, in exchange for free food and lodging during the event.
Now on the day of the event, almost all of the volunteers just failed to show up. When they were called, they said they were pissed off and wouldn't do it. In the end, the organisation had to hire a professional security service for lots of cash.
Could the organisation ask for compensation for the volunteers failing to fulfill their side of a contract? Normally, if somebody fails to provide an agreed-on service, the other party can buy it from someone else and the first party has to pay the extra costs.
It seems that Art. 394 OR says service contracts can also be valid without payment, if that is agreed on. Not sure if that article is applicable to this situation, though.
Maybe important: There's no formal requirement for service nor for work contracts. So either of them can be formed by oral agreement.