Mike Budenholzer has received a $25,000 fine for making contact with referee Ben Taylor.
But the National Basketball Referees Association believes Budenholzer should have received a suspension.
The incident occurred on Saturday.
"Referees operate in environment in which an influential NBA team owner has repeatedly mocked the efficacy of fines as means to change bad behavior. Coaches should compete by creating better teams, not by physically intimidating officials."