Matthew 22:33

‘And when the crowds heard it, they were astonished at his teaching.'

It was the crowds who were impressed and astonished by His teaching. This indicates that the Sadducees were rather annoyed by being unable to reply, rather than being impressed. They were not willing to be convinced. they were merely silenced. For however strong the argument, those who do not want to hear, will not hear. It is also a reminder that the crowds were present throughout all these goings on.