Unfortunately, the worst offender of this is the federal government. Essentially any federal position, regardless of actual job position, requires a background check.
Does a background check in the US imply that they'd never consider anyone with any blemish on their record whatsoever? Surely it just means they have to make an informed decision.
No, but federal jobs usually get dozens or hundreds of applicants. Removing felons is usually one of the first filters they use to narrow the field.
(Insert snide remark about elected/appointed politicians here.)