As far as including .hip files, I can see how that helps a specific user with a specific problem (and we do get to share in the postings) but I prefer to ask and answer questions in a way that covers the general ideas behind the issue. Sometimes, with how complicated Houdini files can get, I understand there is no other way to debug it.
Since with Houdini the same end result can be done in many different ways, most of the time a hip file is very useful. While it may only help that specific user for that specific problem, the solution can be insightful for many other possible scenarios.
For any question/answer dialogue there has to be some context. If it's related as an example, to a specific node - then something like a .hip file is not necessary as the ‘context’ is understood.
In other cases a .hip file is not needed if a very experienced user reads the question and is able to answer simply because they seen similar queries before and with their own experience are able to more than likely ‘guess’ the context and provide a possible answer.
However, those who read the answers other than the op might not be able to benefit - without a .hip file.
Also, in the case of a large scene file the original poster - if they took the time and did some work in reducing the file complexity and attempting to isolate the issue; and I am only speaking from my experience - Many times that solves the problem in that you discover where and what the issue really is.
Otherwise posting that simplified .hip file has a much greater chance of getting a response.
After which, more ‘general ideas’ can be discussed and prove useful because there is a context ( .hip file )