Why does the automotive industry almost exclusively use silicone-free release agents on thermoplastic components?

Since thermoplastic based parts produced for the automotive industry generally have to be treated further, it is important to ensure that silicone-free release agents are used. Silicone based release agents will cause the surface of interior parts to seem oily, and silicone is difficult to remove from the plastic surface. The risk of paint shop contamination is also very high and silicone can shut down an automotive manufacturing paint shop fairly easily causing production delays and incurring significant expense.