A better trick I discovered when I used to work in an environment closer to this was to always give the person requesting help some trivial but sincerely related task to do before you can help them, e.g. "can you just write down all the steps in the process before you get stuck, it will help me solve the problem", or "Hmm... I'm not quit getting the issue, can you draw me a diagram and then get back to me". This acts as a great filter for people that are just helpless versus people that really need help. And if anyone complains to the boss that you aren't helping, you can say "oh well did you do task X? that's really all I need from you to get started"