Unfortunately this is true; and if you're not careful with your time, a lot can be wasted by people who realize "I can email so-and-so instead of putting in 5 minutes to finding the issue myself".

They're usually pretty courteous in their interaction, which makes it all the more difficult to be "rude", in my case, by adding an exponential falloff in response times - after I realize what's happening, I tend to take a little longer for each reply so they figure out it's faster to just do the research on their own most times.