Kwok's lawyer said that the crime was committed out of Kwok's craze for buses, and that the items his client - a "super bus fan" - stole were not available for sale.
But Deputy Judge Don So Man-lung said: "[These plates] can certainly be made."
"You can make all kinds of advertising signs these days. Why not this one?" So added.
He was told that Kwok only wanted the authentic version.
Kwok has been remanded in custody and will be sentenced tomorrow.
The other two, Marco Yiu Ho-yin and Chan Ho-yin, are expected to face trial in July, with a preliminary hearing scheduled in April.
Prosecutor Ivan Shiu said the three met online a few years before the offence.
While Yiu and Chan were working for KMB at the time, Kwok was an ex-employee.
Shiu said that on February 12 last year, the trio arrived at 1.30am and waited at the Siu Hong Court Bus Terminus in Tuen Mun for staff to leave.
Chan then allegedly cut the door lock of the bus office and they stole the items inside.
Meanwhile, the prosecutor said, Yiu went to a nearby bus station to drive a double-decker bus over and pick up his accomplices.
They then proceeded to Leung King Estate Bus Terminus and Tuen Mun Station Public Transport Interchange for more break-ins, Shiu said.
He said the three men hid the stolen items in a decommissioned bus parked at an open area in Tsz Tin Tsuen.
That vehicle was bought by Kwok and six other friends, according to Kwok's lawyer.
- South China Morning Post