The first story is All You Can Eat by Harvey L. Bilker and Audrey L. Bilker.
As the story progresses the alien continues to eat prodigious amounts
of food, to the dismay of the establishment's other customers and
eventually the restaurant owner himself. Eventually the alien reveals
that he hails from a distant planet that has been wrecked by
pollution, and now its inhabitants have to send agents across the
galaxy to consume and "kinergize" food back to their starving
population.
Review: Children of Infinity
The second story is Harrison Bergeron by Kurt Vonnegut Jr.
It is the year 2081, and all people have been made 'equal' through the
use of physical and mental handicaps. The United States Constitution
mandates this equality in the 211th, 212th, and 213th Amendments, and
the law is enforced by Diana Moon Glampers, the Handicapper General.
GradeSaver: Harrison Bergeron Summary
While 'Harrison Bergeron' has been collected endlessly, 'All You Can Eat' appears to have been collected in only one anthology; Children of Infinity.