IIRC there is a shortage of truck drivers.
I will see if I can find the article again.
Here is what I found:
https://www.joc.com/special-topics/driver-shortage
https://www.washingtonpost.com/news/wonk/wp/2018/05/28/america-has-a-massive-truck-driver-shortage-heres-why-few-want-an-80000-job/?noredirect=on&utm_term=.44414eba02e8
https://www.npr.org/2018/01/09/576752327/trucking-industry-struggles-with-growing-driver-shortage