Businesses are already regulated in who they can hire and on what terms– for that reason there are child labour, minimum wage and anti-discrimination laws. These kind of regulations come both from national governments and the European Union. Governments have always had this right.  This policy is therefore not damaging freedom of choice any more than many other regulations. It will most likely not be necessary to make taking on the temporary jobs compulsory because the government is paying for it and how many companies will turn down something that is essentially a subsidy?