Leave Me Alone

This character trait of mine has been slowly developing under the radar. I hope it doesn't make me an asshole, although I half think it does.
The first time I really noticed it was during a trip to Chicago to see Hoops. Waiting for my (now beloved) Megabus from Chicago to St. Louis, when I a trechcoat-clad gentleman rambled up to me selling copies of the FREE satire magazine, the Onion. Now, I buy socks, lighters, photos and loads of other junk from homeless/fell-on-hard-times people. But, my reaction to this guy, after a second's glance at the Onion copies he was hawking, was so instant and second nature that it shocked me. Even this guy, a tougher character than I, looked taken aback by my immediate and jaded hand wave without a nanosecond of eye contact.
I have to say, I didn't feel bad at that second, but while running back and forth from Union Station and the actual bus, I realized that I had been pretty mean. This was placed in high relief when the next guy approached quickly forked out a buck to acquire a copy of the free mag. Is he naive or have I simply internalized my wall to a horryfying extent?
Now, I am still nice to people I meet and feel like I have time for any person that has a genuine heart. So, on that note, I feel fine. However, this trend does make me slightly edgy, as it seems to indicate that my dismissiveness has reached new hights, which brings me to today.
Sitting on the Seoul subway, which I rarely ride since I live 2 minutes from work, I saw a middle-aged white man get on the train (which is not too hard to spot here). For the next five minutes, he fumbled around with a variety of knickknacks: first, an apparently new set of keys and a bunch of coins; he later moved on to papers, dropping several pieces of paper while doing so. He looked utterly echausted, based on how he put up his bag on the rack, and I felt a little sorry for him, for what reason I don't know.
Then, just under a minute from my destination, he came over to me, thrust a pamphlet my direction and told me, in Korean, to please take a look at the literature. Sure that it was another Morman or other religious wacko, I glanced at him sideways and said "no". He assured me that it wasn't religious, but again-another snap judgement, free from any detectable reasoning process- I told him no.
At this point, it got sticky, as there was a whole lot of Koreans watching the two foreigners going through a relatively unpleasant dance--he being more assertive than most Koreans would stomach, and me being more hostile in return than most Koreans would want to be. Whatever his cause was, I didn't look long enough to see. I just immediately brushed him of. And, at this point, he pushed the paper/pamphlet in my direction, assuming I would take it (had he been trained to believe the generally true rule of thumb that people will instinctively take something handed to them?). Instead, I continued to brush off the request, but inadvertently knocked the paper down, while simultaneously saying I didn't want to see it.
"Why?" he asked, in a slightly damaged voice.
"I'm getting off now," I responded with a coldness and detachment worthy of HAL in his better days. I didn't really look at anyone after that, but I could feel the tension in the body language of everyone on the train (and what a sight for them! Foreigners in conflict! Even better than regular foreigners!).
Leaving the train, I felt no remorse, but after a scolding by the wife, I wondered if I had been a little harsh. Half of me thinks that there is nothing a random person on the subway is going to give me that I will want (something that has proven to be true 99.9 percent of the time). The other half wonders if guy will think about this as much as I am.