very good question . The research if it is useful for the masses, becomes the instant useful and popular. that is one aspect. second is these types of research should be encouraged and funded by the government, bcos these research will have a mass appeal in future.
application aspect of research is very important factor which we should consider while selecting research topic. generally we all do but sometimes we ignore it because there are some areas which we are interested irrespective................. topic is having application or not. so it is suggested not compulsory.