Some of what is in the link has not been my experience. I think chigger's prefer to bite where its warm, dark and moist not where the skin is thin. Failing to find a dark, warm and moist spot they will just bite you. I have had hundreds of bites all over my legs. Not thin skin where I got bit. I don't know if chiggers move around but I surely have seen where a nest of them had collected and then gotten on me.
I was wearing trousers treated with Permithren and which killed the chiggers. I stood and watched them die and fall off.

I admit I took great joy in watching their demise.
I have seen ticks sense me and follow me.

They don't just sit and wait. I was taking a break one day on the gravel road. I saw a tick moving towards me and every once in awhile the tick would stop and rear up and wave its front "legs" It then would move towards me again. This went on a few times. I then moved 90 degrees out of the way to see what Mr. Tick would do. Mr. Tick was confused when I moved but he waved his little legs and eventually found me again and started moving after me. I moved the chair again.
He found me again.
I smooshed him between two rocks.
Benydrel both the gel and the pills helps. The gel really helps since it is easy to spread over large area of chigger bites. Frankly, scratching the heck out of the bites seems to reduce the itch. Infection is a worry but the itching is unreal. Ya gots to do something. For me once I have scratched the heck out of the bite it leaks white fluid. Once that happens the itching seems to decline quite a bit.
Later,
Dan