Your feet are the foundation of your body, and like the foundation of a home when it is not aligned properly, stresses get transmitted throughout your entire body causing it to wear and tear much faster.
Finding and maintaining proper feet/arch position during activities is extremely important for optimizing the transmission of forces up the kinetic chain while minimizing stresses. That said, orthotics are often overprescribed and sometimes becomes the crutch that results in further weakening of the feet muscles.
Those assessed and determined orthotics can be beneficial, will receive manual therapy to realign the feet and lower extremity before they are casted for the orthotics. If orthotics are felt not to be necessary, then the assessment would be billed as a Physiotherapy session.