In fact we can and do have it both ways. We encourage homework-like questions that ask about the physics concepts pertinent to the question. We discourage questions that ask us to solve someone's problem for them. What we like and don't like is, of course, entirely up to us (meaning a majority of our trusted users) to decide. You can see our decisions at thisthis meta post. The appearance of non-consistence may (and I stress the "may" since I cannot be sure about anyone's understanding but my own) be due to a difference between how you understand what we accept and what/why our standards for question are and how we understand it.
replaced http://meta.physics.stackexchange.com/ with https://physics.meta.stackexchange.com/
replaced http://meta.physics.stackexchange.com/ with https://physics.meta.stackexchange.com/