Somebody wants to open a shop near another equivalent one. He estimates that the other shop will still stay in business just fine but may have to fire a few of their workers. Can they protest the opening of his shop because for those workers it is Mafsid Chiyusei Legamri?
This is an interesting question. It stands to reason that the concept of Mafsid Chiyuso Legamri, which originates with the Aviasaf and which is ruled by the Chasam Sofer and others, applies specifically to a storekeeper, who will lose his income and will not be able to recover.
In the circumstances described by the Aviasaf, the town shoemaker / baker / blacksmith stands to lose his only possible income. This does not apply to a worker, who can find work with another store or another company etc. Therefore, the idea will not apply to workers but only to the owners of the store.
Moreover, having to think about companies cutting down etc. would be crippling to competition, and the modern market requires a healthy level of competition to ensure fair pricing etc.