It doesn’t make sense to consider indiscriminate withholding of services through a strike not “unchecked power,” while selecting specific targets (which is far less disruptive to the market as a whole) as such.

It’s also not an arbitrary choice. It’s a business that’s clearly in dispute with another union, that this union has decided to intervene on behalf of. It’s not like they’re striking against a company that was just minding its own business.

Perhaps there can be labor relations boards and anti-discrimination regulation and such to prevent abuse of selective striking, but this is obviously a situation where everyone is a player and knows what game they’re playing.