No, those examples you give would be taken care of as part of the "B" part of the test. Plumbing and website design is certainly not the main business of restaurants and real estate agents.
The problem becomes if you need to hire a freelance programmer to do some work for your software development company. There the "C" part of the test becomes a lot more of a gray area IMO.
>The problem becomes if you need to hire a freelance programmer to do some work for your software development company.
In that case, C is irrelevant because you've already failed B AFAICT. This law makes it so that it's simply not possible for a software company to contract out software jobs to individuals. It has to either contract the software to another company, or do the job in house with W2 employees.
C, if my reading is correct, means that (ignoring licensing issues) you can't contract a carpenter to fix your plumbing.
The problem becomes if you need to hire a freelance programmer to do some work for your software development company. There the "C" part of the test becomes a lot more of a gray area IMO.