Although they sound completely normal to native speakers, to the outsiders, they are nothing but a meaningless string of letters. Many of these subcategories contain their own very colorful expressions. Slang and idioms are used throughout the world, and many of our own common expressions have equivalents in other languages in other places. In fact, business is notorious for creating a slang or jargon of its own. Clearly, a nonnative speaker who doesn't have a working knowledge of business jargon would be at a loss.
Sports jargon is particularly widespread in business since sports permeate American culture.
This may also be related to the fact that both sports and business in the past have been predominantly influenced by men. After years of presenting to numerous teachers and leading discussion groups, I have found that the vast majority of teachers feel that familiarizing students with slang, idioms and even some vulgarities is much more desirable than having students pick up this type of language haphazardly on the street. The main concern is that students often hear vulgar or provocative words used loosely and gratuitously and, therefore, don't understand the full weight and connotation of a particular term or expression. The unsuspecting student may find himself in an embarrassing situation. However, having first been exposed to this type of vernacular in the classroom, these potentially embarrassing situations may be avoided.