Why can't I ask hypothetical questions about situations that can't happen in the first place, if I'm interested in the resulting phenomena and/or said situation will cause?
The simple answer is that science is a description of reality and not a speculative discipline. If you are speculating about a scenario that is not well understood, you can do it as part of hypothesis testing, but if something is well understood, like energy conservation in most regimes, then asking what would happen if it was strongly violated is simply not a scientific question. We can't know what would happen if the laws of nature would not be what they are. Pretty much everything in science is, directly or indirectly, strongly intertwined with everything else. Every one scientific construct is checked and cross-checked for consistency with everything else over and over, again. It's a tightly woven logical fabric. Take one thread out and the entire construction unravels in ways that would require a complete reanalysis that may be just as complex as the process of building what we have now in the first place was... and we would be lacking any guidance from nature, which would turn it, at best, into a field of mathematics.
If you are asking about violations because you are trying to understand the significance of a law or a particular phenomenon, then you can always formulate the question in another way, like
Why is the law of energy conservation so fundamental in physics?
Can we imagine ways in which the law of energy conservation may be broken without unravelling all of physics?
These are actual questions that some physicists are asking for good, both theoretically and experimentally, and they do have important answers.
Sometimes we get questions from science fiction authors (or people who are toying with the idea of becoming one) who want a particular plot device validated by science. My advice for those would be to go one of two ways:
Invent a world with completely different physics. That's safe and it gives you many more means of artistic expression. Some of the best science fiction and fantastic literature is based on that premise.
If you can't do (1), stick slavishly to textbook physics.
Every attempt to walk the fine line between the two that I have seen ended up unmasking the author's inability to stick to his or her own logic. If you need examples for the latter type of literary catastrophe, pretty much every story ever written that has an "ansible" in it belongs into this category and so do almost all stories about time travel. It is extremely difficult to make up scenarios where a plot device lets the author do one particular thing but wouldn't give rise to a much more logical story line that uses the same device in a different way. Unless you are very good at constructing self-consistent story lines (in which case you would likely be making millions in Hollywood, already, and wouldn't have to ask us), don't go there.