| | Re: The couple has arrived
This often drives me nuts, too. American English and British English view group nouns differently.
In most cases, American English considers group nouns (government, staff, team ,etc) as singular. For example: The team is doing well this year.
British English often uses both. I think BrE uses singular for groups of people doing personal things, such as deciding, hoping, thinking, or wanting. I also think BrE uses singular verbs if the determiner is singular (a/an, every,the, etc).