I think there is absolutely no question, a programmer that is employed by a company is working for that company and 100% of what is coded is property of the company. To take that code and use it outside of company use would in fact be theft. Obviously the contents of someone's head is property of that person, so having gained expertise in programming is not owned by the company, but physical or electronic property that was developed is not the property of the employee.

When it comes to a subcontractor, that is where the "contract" part of the relationship comes into play and is obviously of great importance. A subcontractor could be brought in to behave more or less like an employee and therefore produce code who's IP is 100% the company, or perhaps they will be retained on a basis where there is joint ownership or no ownership by the company, except for executables. In such a free market framework, the contractor could be compensated appropriately depending on the exact nature of the contractor's work.