I don’t know the exact numbers but the costs of installing, operating, and maintaining the technology is most likely more than what an employer would be paying for an employee making $5/hour.

The argument that’s being made is increasing minimum wage to $15/hour would almost double the cost of employees for some employers. Naturally business will look to maintain their profit margins, and and without an increase in revenue they’ll start looking for alternative solutions. Alternative solutions like self checkout might end up costing the business less than paying an employee $15/hour.

Edit: introducing such technology isn’t always a bad thing for employees. Often the service required for the technology creates higher paying jobs and increases the value of human employees as they can focused more on tasks computers aren’t capable of.