Unfair Employer practice to force Employees to move

One of my friends mentioned to me about his employment situation in which they are forced to relocate to Texas or couple of other Southern states in US or asked to leave the company. Company has a big presence in NY city and they are doing cost cutting via relocating. He has been part of the company for 15+ years and now across multiple teams they are giving out notices which are pretty much like either relocate or leave the company. In-case they choose to leave they do NOT get any severance package. They are presenting impossible choices to people in most of the cases people in his company are just forced to leave as it is really hard to move, sell homes, setup kids schools and all other things in short 3 months notices.

My question for HN community here is - are such unfair practices allowed to dodge severance pay? Also is there anything people can do legally to stand their ground against unfair practices?