Afro-Caribbean Kenroy Wallace believed that he was the target for racist comments on the Arriva bus from Whitby to Loftus, said prosecutor Martin Towers.
Mr Wallace was pushed over a seat, and the bus was stopped in Loftus where his four abusers got off and he left it soon afterwards.
There was another confrontation in the street, and the police later arrested the members of the group on suspicion of causing an affray, Teesside Crown Court was told.
Lawyers for three of the defendants said that the words which caused offence to Mr Wallace were not directed at him, and the incident was probably because they had been drinking too much.
Katherine Hogg, 37, a mother, Callum Hogg, 18, and Stephen Wood, 19, all pleaded guilty to causing an affray on the bus on July 10 last year.
Wood also pleaded guilty to an affray in the street and to a common assault on Mr Wallace.
Judge Howard Crowson told them: “This was a disgraceful course of conduct.
“If I had thought this was motivated by race I would have been thinking about custodial sentences, I do find that sort of behaviour abhorrent, and most people do.
“But it wasn’t, although Mr Wallace thought it was.”
Wood, of Coverdale Buildings, Brotton, was given a 12-month community order with supervision, 150 hours’ unpaid work, an alcohol treatment requirement and ordered to pay £100 compensation to Mr Wallace.
Callum Hogg, of Queen Street, Brotton, was also sentenced to a 12-month community order with supervision, alcohol treatment and £100 compensation.
Katherine Hogg, of Bank Street, Guisborough, was ordered to pay £100 compensation with a 12-month community order with supervision.
A male juvenile, who cannot be identified for legal reasons, was sentenced to a referral order in July after he pleaded guilty to affray.