Topic: Street pass Miis not showing up?

Sorry if this is a stupid question..but I don't use my 3DS often. I took it with me to Six Flags today and got like 20 street passes, but only three showed up in find me/puzzle game! Why didn't all of the people I street passed show up? Same thing with when I went to the Best Buy event hosted by Nintendo, where I got like 50 street passes, but only 18 showed up in Find Mii/Puzzle game.

What's happening?! Also, I've only street passed like 70 people or so.. (I only started on Wednesday), but I have 152 in my plaza. How did that happen?!
I don't have the 3DS manual or anything because it wasn't mine originally, it was given to me by my uncle. Thanks in advance!

When you get StreetPass hits one day but you don't use them, and then the next day you get more StreetPass hits, you'll need to play with your old StreetPass hits before you play with your new ones. So, for instance, I met four people on StreetPass on Sunday. I didn't use them for any games and I get more StreetPass hits on Monday. Before I can use the StreetPass Miis I received on Monday, I would have to play with the ones I received on Sunday.

With your other question, I don't know the full answer, but that's happened to me too, even before I used StreetPass myself! My theory is you receive the Miis through SpotPass, since I received my first StreetPass Mii Plaza Miis after going online in Mario Kart 7.

Oh, Mario Kart 7 must explain why I have 100+ miis in the plaza!

But even after I used all of the heroes that showed up in find Mii, I only used 18 out of the 66 people I streetpassed! Same thing with puzzle swap!

Three things:

• People could have streetpass turned off for the plaza, no idea why
• It's possible to randomly streetpass with other games but not the plaza with a person (or visa versa)
• Miis will come in from other games if you haven't disabled that feature