I know a lot about this subject, you do have to be disabled but do not have to be on any government assistants.

Disabled meaning that you are physically or mentally impaired in a way that substantially limits one or more major activity such as seeing, hearing, walking, getting the mail, ect. If you aren't disabled you can't have an ESA

Keep in mind ESA have to also be well behaved, if it makes a lot of noise or smell they still have the right to ask that you leave.