If the salary is higher for the same position then the company has been underpaying you, if the salary is lower then they are trying to get someone on the cheap. Either way I'd want to know if this situation.
I'm not asking for an exact figure just a rough range as everything is always up for negotiation.
"Either way this does no good neither to you or the company." <- I have to disagree there, you should always know if you are underpaid or that your company tries to get similarly skilled individuals for lower salaries.
Not revealing salaries I think hurts companies recruitment processes more than they realise, how many great candidates passed on applying due to not wanting to have to dig a figure out of the company. I assume they think by not revealing salaries they'll get applicants who could command the highest rate they are willing to pay PLUS 30% more applying and being offered the job and then going 'yeah I'm fine to work for 30% less'.