Why do you assume that? Consider that if the story of Jesus "cleansing" the temple is true, that this would have been something Pilate would have heard about. The city was having a holiday with a gazillion pilgrims visiting. It was very important for Pilate to keep his thumb on things, lest the city devolve into chaos. So someone going into the temple and committing vigilante violence, committing assault and vandalism, is certainly the exact sort of thing that is going to be on his radar. I can't know what actually happened, as I do not think the legends are reliable. But it certainly seems reasonable to me that this action by Jesus would have put him on Pilate's radar as a troublemaker who needs to be dealt with.
Vigilante violence? Committing assault and vandalism?
Matthew 21:12-17
English Standard Version
Jesus Cleanses the Temple
12 And Jesus entered the temple[
a] and drove out all who sold and bought in the temple, and he overturned the tables of the money-changers and the seats of those who sold pigeons. 13 He said to them, “It is written, ‘My house shall be called a house of prayer,’ but you make it a den of robbers.”
14 And the blind and the lame came to him in the temple, and he healed them. 15 But when the chief priests and the scribes saw the wonderful things that he did, and the children crying out in the temple, “Hosanna to the Son of David!” they were indignant, 16 and they said to him, “Do you hear what these are saying?” And Jesus said to them, “Yes; have you never read,
New International Version
Jesus Clears the Temple Courts
13 When it was almost time for the Jewish Passover, Jesus went up to Jerusalem. 14 In the temple courts he found people selling cattle, sheep and doves, and others sitting at tables exchanging money. 15 So he made a whip out of cords, and drove all from the temple courts, both sheep and cattle; he scattered the coins of the money changers and overturned their tables. 16 To those who sold doves he said, “Get these out of here! Stop turning my Father’s house into a market!” 17 His disciples remembered that it is written: “Zeal for your house will consume me.”[
a]
Mark 11:15-19
New International Version
15 On reaching Jerusalem, Jesus entered the temple courts and began driving out those who were buying and selling there. He overturned the tables of the money changers and the benches of those selling doves, 16 and would not allow anyone to carry merchandise through the temple courts. 17 And as he taught them, he said, “Is it not written: ‘My house will be called a house of prayer for all nations’[
a]? But you have made it ‘a den of robbers.’[
b]”
18 The chief priests and the teachers of the law heard this and began looking for a way to kill him, for they feared him, because the whole crowd was amazed at his teaching.