"This is a circus, and not a café."

Translation: Это цирк, а не кафе.

[jumpthewalls]

Russian Ring-Masters obviously do not take kindly to loitering

[Jaknasrav]

Why are you drinking coffee in here? Stop it! Pay attention to the show!

[SilverCharacter]

Usually one would say it vice versa.

[Diorden]

Can "а" and "не" be switched, or is this word order necessary?

[Zhenya_Melamud]

no, а and не cannot be switched here.

just for information: Это не цирк, а кафе means the opposite - This is not a circus, it's a cafe