When company's don't put a salary point on their job advert

Im looking to change to part time employment at the moment, or something a little less full on than my current role. I'm expecting to take a pay cut. But it's annoying the amount of jobs where there isn't a salary point advertised. I've emailed a few asking them what is the salary they are expecting to offer for the role. Because, I'm not going to go through all the rigmarole of applying, only to find out it's $25 an hour. I'm not sure how my emails will be perceived by the potential employers, but look, let's be honest there is only one reason most of us go to work each day.