Yes all the currency exchanges around the world (at least the reputed ones) do this as a part of their operating country's AML policy. The exchanges are required to report the transactions which raises a flag to the operating country's central banking system too.

AML rules can be complex, but it also has trivial rules like if the occupation of a person and the amount of the money he exchanges do not make sense, the transaction will be flagged and reported to the central bank. The transaction will go through, but will be reported to the central bank using a webservice or as a monthly report. Its upto the central bank to investigate it further.