Buddhist "Missionaries"?

It's a warm Sunday afternoon... I just returned home from a short jog/ walk... Shortly after I returned, I was on Skype talking to me sister when my doorbell rang. There were these two gentleman, I assumed salesman, and they were speaking to me in Japanese. I said, "I'm sorry. I don't speak Japanese."  Then they replied, "We know a little English." They take out their smartphones to translate something. And they asked if I was Christian. I said, "Yes," and then they asked me to go to a Buddhist event.  So were they trying to convert me to Buddhism? Are there buddhist missionaries? I apologized and said no, and then closed the door.  Then a few minutes later they came back. One gentleman had a translation on his phone saying something along the lines of wanting someone to practice English with, and if  we could be friends.  I said no, but maybe someone I know would be interested. So now I have their names and their Line IDs.  It was quite strange... Lesson... NEVER never NEVER never OPEN YOUR DOOR. I should've learned from the previous situation. It was an interesting situation though... Who would've known...