Answer:
Often wandering the streets, this group of people cannot afford to be choosers.
This type of corn swells up and bursts into a crisp puff when heated.
What has fingers and a thumb but no hand?
I know a word of letters three, add two and less there will be.
What devours all and can kill a king. Destroy a town and crushes mountains down?
People take me on walks and I run and have fun. What am I?