One of my clients has recently bought a new pair of trainers after having her feet assessed in a sports shop. She was told that she was a 'pronator' and that she needed to pay extra for the 'correct' trainers. Now that's all well and good. I agree that some people do need specialist shoes. But they need to have them for the right reasons.
Now everyone pronates (or they should). It's a necessity. We pronate as a shock absorption mechanism. It's OK to pronate.
Now the key is that we need to re-supinate in order to have the stability to move ourselves forward. There are some people who lack this re-supination due to the bones in the feet not 're-locking' as they should. They have a 'floppy' foot. I'm one of these. I therefore need a bit more stability.
But there are some people who are so called 'pronators', who have to have the foot in this way because other areas are not moving the way they should be. As a consequence the foot is compensating for the lack of movement further up the body. Now if we get those people moving the way they should be then there are many who are no longer 'pronators'. They don't require the extra support (and can buy a cheaper pair of trainers after all).
All I'm saying is that if someone tells you that you are a 'pronator' be sceptical. Ask questions. Find out what is really going on with the whole of your body. Make sure they are not just looking below the knees.