From an employer's point of view there are many good reasons not to state a salary range, the 2 most obvious ones being:

- once you state clearly what your max is, why would your preferred candidate settle for anything less?

- why would you want to exclude good candidates willing to accept lower comp than what you thought your min was?

So then some places are a candidate's market... well maybe employers have to adapt, but I can see why they would not want to.