1. It allows me to understand that I am not the only one who doesn't understand the terminology involved, allowing the discussion to be more educational and inclusive.
2. Sometimes searching for terminology is ambiguous and without prior knowledge of the subject domain, can result in lack of confirmation as to whether the definition is the same as the one in the article.
3. For one person to ask here and have it answered, can save 100 people having to search for themselves when reading the comments.
Better yet, as I see people do around here from time to time, go read a brief synopsis and then post a "For other people who didn't know what BGP was: BGP is ....". I'm not for creating a hostile stuck up community but rewarding pure laziness seems pointless to me.
"Be civil. Don't say things you wouldn't say in a face-to-face conversation. Avoid gratuitous negativity."
There are things people don't know. I find xkcd's attitude a useful one to keep in mind: