I have attended a decent number of TCS conferences. It is good that researchers solve difficult problems. However, I am often interested in the reason why a problem is interesting in the first place. So, I often ask the presenters about some real life application of the problem that they have solved.
For example: If somebody has studied the Independent set problem on planar graphs of degree at most 4. Then, I ask why a planar graph of degree 4 is an interesting use case. Note that I am aware of why the independent set problem is interesting in general graphs.
However, the presenters usually do not answer such types of questions properly.
The following are the replies that I often receive:
They do not give the answer and simply say that it is an established problem. It makes me feel dumb.
Some people admit that they do not know about it and they are only studying the theoretical side of the problem.
Some presenters enthusiastically answer the question and give more details than I expected.
Should I avoid asking such types of questions?. Should I simply believe that the problem will have some application in the future, if not now? Then, how can we know if some problem is more interesting than the other, if we do know its usecase yet?