As a foreigner that does not speak Korean, the first time/s that I heard this, I assumed the man was saying "The end is here. It's happening. The North has attacked. Make your way to your embassy Kristen, say goodbye to your loved ones". I pictured some police officers walking around the roads making important announcements.
I didn't figure out that the noises were vendors until about a week after I got here and I didn't know they were coming from trucks until yesterday. All these men are doing is trying to get people to come buy things from them, so in reality they're probably saying "Super cheap prices. Come buy some fruit."
Culture shock.