Alot of my friends left to start food trucks, street stands, etc... Keep in mind where I live (a cold part of Canada), you can realistically only sell street food for 4-6 months out of the year. They would all make $60,000 to $100,000 in a season, and now a few of them have brick and mortar restaurants to their name.
I worked a street food stand for a festival awhile back, we made $3000 in a day (split 2 ways).
Street food doesn't scale too well, and there are a whole slew of downsides, but if you can figure out an efficient way to make tasty food, you can make a lot of money and there's only a small barrier to starting out (likely less start up cost in China).