Do Japanese people tend to be vague even when talking about people their listeners know?


I've noticed that a couple of my Japanese friends, when talking about their
plans, might say something like 「友達に会う」, "I'm meeting a friend", even though
the unnamed "friend" is someone we both know. It's a little jarring when I
know from another conversation exactly who they're meeting, or if I find out
later who they were meeting, and it's a mutual friend.

What I expect from my own experience as an American is, for example, for them
to say something like 「ゆかちゃんに会う」, "I'm meeting Yuka", because to me "friend"
or 「友達」 sounds like someone I'm not expected to know.

The effect is that it ends up feeling like the people they're meeting is being
deliberately kept secret for some reason I can't fathom. But, is it simply
normal to leave out the names even of mutual friends as unnecessary
information?




It's not uncommon for the Japanese to use the following in the regular
conversation. Mostly they habituated not discussing about their personal
things in more detail with others  
用事があるから早く帰ります。 I will leave early because I have things to do.  
予定/約束があります。 I have appointment/meeting (It can be any type of meeting)  
体調が悪い。Ill/Sick (Does not talk about what kind of ill)




It's not uncommon for the Japanese to use the following in the regular
conversation. Mostly they habituated not discussing about their personal
things in more detail with others  
用事があるから早く帰ります。 I will leave early because I have things to do.  
予定/約束があります。 I have appointment/meeting (It can be any type of meeting)  
体調が悪い。Ill/Sick (Does not talk about what kind of ill)

