What is one specific way that living in a company town prevented workers from forming organized labor unions?

In the early 1900's, a company often provided a company town, a place where the worker could live in the near working location (usually like a mining location)

The workers usually were lured by the promise of high wage.

But here's the thing, in company town, a source of living usually can only obtained in a company store, and the cost is really high.

So instead of getting a high wage, the workers trapped in huge debt to the company, creating some sort of slavery that they have to work to pay off their debt to the company

Techincally, the company could easily bring those workers to the court (even though is very cruel, they obtain the debt in a 'legal' way), so basically workers cant do a thing