"I strongly condemn such racism and violent behaviour. Local businesses are already doing [it] tough through the prolonged lockdown. Now another attack?!"
In a statement to Yahoo News Australia, Victoria Police said there was no evidence the note was connected to the vandalism.
A 28-year-old Clayton South woman was arrested for the vandalism on September 7. The store is on the same strip where the businesses were vandalised.
The note called for Chinese people to "go back to where you came from".
City of Monash Mayor Stuart James shared the note Twitter and said there was "no place in this country", or in the City of Monash for the racist views.
"I am absolutely filthy and disgusted at the letter below that was posted on a shop window in Clayton not that long ago," he tweeted.
"This country has been built on the back of migrants from all around the world who came here seeking a better life for them and their families."
One twitter user questioned why the note was being shared on Twitter.
"Why are you sharing this hateful message to all of Twitter? Just rip it up and trash it - you are extending their message to a larger audience and inciting similar minded people."