There's no need for unions. We treat our employees farily. - US businesses
You owe us $20K if you leave this job - Also US businesses

I can't read the article but I would have to think consideration has to be demonstrated in exchange for requiring a reimbursement from a worker who has left.
I used to work for a company that used an extensive training program for some new hires (not me). When they hired them, they signed a contract that stipulated if they left their position for another sales job within 5 years of employment, they owed money back to them.
#4 | POSTED BY EBERLY

I understand educational reimbursements that are pro-rated and provide transferrable benefits to the employee such as a degree or certification. I have taken advantage of such programs offered by employers. It is reasonable that if an employer is willing invest in the improvement of their employee that the employer be granted on a return on that investment. The article even notes that historically that is what these type of contract clauses have been used for and cites federal case law where those clauses have been upheld. But that's not what is going on with the contracts described in this article.

Many of the clauses referenced here include things that have traditionally been considered cost of doing business expenses such as the cost of hiring a replacement, governmental mandated training that does not provide transferrable benefit to the employee and even trying to charge employees for the normal OTJ learning that occurs in any environment. One such example included a salon owner claiming that the time she had one of her new employees wax the owner's legs that constituted reimbursable training costs for the employee. They also list cases where the clauses have been used as deterrents to employees suing over labor violations such as unpaid OT, harassment, dangerous work environment, etc. Another example includes a contract for a health care worker that includes unspecified costs such as having to pay the difference between their salary and the cost of their replacement during the remaining term of the contract.

In some of these cases the reimbursement requirements are placed upon lower income employees and would result in their earning sub-minimum wage pay when reimbursement is factored in. In other cases these contracts sound like indentured servitude and may violate human trafficking laws.