Antique furniture restorer Mark Bailey was convicted earlier this month of sending a letter "smeared with faeces" to cause distress or anxiety at VAT offices in Southampton.
Bailey denied the offence and was rebuked by magistrates for wearing a t-shirt with "Come to prison, it's fine" and "Customs and Excise stabbed me here" written on it.
On Monday he was also sentenced by magistrates in Cheltenham to 100 hours community service.
Sentencing Bailey, Derek Morris said he was surprised to see such a respectable businessman appearing for such a "peculiar and disgusting offence".
"We find it so strange that a gentleman of your calibre and standing in the community should have conducted such a course of action," Mr Morris told Bailey, of High Street, Winchcombe, Gloucestershire.
The excrement-smeared letter was not opened by a VAT official but by a 19-year-old postal clerk "who was revolted by it", said Mr Morris.
Bailey's solicitor, Simon Hett, told the court that Bailey had "good reasons, albeit mistaken ones, for his bizarre reaction" to the VAT demand.
'Intimidatory tactics'
Bailey was a traditional craftsman whose business was going through a very difficult period and he found the intrusions of the VAT officials intolerable, said Mr Hett.
"He wanted to convey his disapproval of the Customs and Excise's intimidatory tactics towards him," he said.
After the hearing, Bailey said VAT inspectors had behaved "like Stalin's KGB" in chasing him for tax they claimed was due on his car.
"They subjected me to a five-hour grilling. I answered all their questions honestly but then they claimed I had been fraudulent in my claims for VAT back on my motoring," said Bailey.
"Lots of people have congratulated me and no-one has told me I did the wrong thing."