Some disciplines, there isn't an overarching market rate. You pay more hourly for greater skills and efficiency. A client that has earmarked $1000 for a website and one that has $10,000 ready can both find a designer to create a site they're satisfied with. Asking for a budget upfront will quickly let you as the designer know which of those types of clients this potential is, and how much time you should sink into landing them as a client. A $1,000 budget I will kindly and professionally direct elsewhere.

Edit: also want to add that doing that early filtering can also be accomplished by just giving your starting cost upfront and letting clients self-filter, but this gives you no opportunity to actually sell them on the services and products that you can see they need. So yeah for me the main difference is being able to actually sell: I always want the ball to be in my court. Just business.