Foot orthotics or supports are supposed to correct biomechanical issues of the feet and to improve the biomechanics of the feet. There are lots of different kinds of foot orthotics and methods of making them for clincians to use and choose from. Many people need and do benefit from made to order foot orthoses while others may be helped by the simpler and less expensive mass-produced foot supports. What type is best for each individual will depend on exactly what is leading to the problems and what the treating clinician proposes is best for that person. All different foot orthotics have got unique design characteristics and a good podiatrist will attempt and match those up to the requirements of the individual. If this is not done correctly, then there may not be any kind of improvement in the problem.
Foot orthoses aren't without their problems. When they are not the right choice for the individual, they'll likely won't help. You are also restricted by what footwear you can use, in that you need to be able to fit them into the footwear and there might not be adequate space. There are also kinds of shoes, like the flip flops which they just can't be used in. This can cause a challenge in hotter climates that make closed in shoes needed for foot orthoses uncomfortable. You can find options, as an example, the Archies that have a foot support built in. The design of the arch supports in these flip flops are like what you would get in an over-the-counter arch support, but most likely not as good as what you will get from a custom made foot support. Using these Archies do give you a practical option to foot supports, based on where you can wear them and the nature of the biomechanical issue. If you do need to have foot orthoses there is no harm in trying these types of options or raising it with your treating podiatrist to determine what they think.