Charlie Letham, 51, had worked for CrossCountry for nearly 13 years but was dismissed for failing to meet revenue targets selling products from his trolley.
Now rail union RMT is asking members to back strike action in protest at the sacking.
Today, Mr Letham – who has doctors’ letters saying he was suffering from depression – spoke of his distress at being sacked.
He said: “I was absolutely devastated.
“It was my life. I feel let down by the company after all the years I’ve worked for them.
“My doctor tried to support me by sending letters but the company just ignored medical advice.”
Mr Letham said sales from the trolley were “hit and miss” and passengers often chose to buy hot drinks at the station.
He said: “You can’t force people to buy stuff. I’ve taken over £500 some days and then another day it might be just £200.”
Mr Letham, who worked mainly on the Edinburgh-Birmingham route, said the sacking in November had come as a shock. “I had recently lost my step-father and my mother had been diagnosed with dementia, which put me into a state of depression,” he said.
“I saw a company doctor who said they should give me an eight to ten week stabilising period, but when that was up, instead of sending me back for a review, they sacked me.”
The union claimed Mr Letham had been unfairly targeted and is demanding his reinstatement. It said other rail companies did not operate a similar system of sales targets with the threat of disciplinary action if they were missed.
RMT regional organiser Mick Hogg said CrossCountry’s own procedures stated that underlying medical issues must be taken into account, but have been ignored.
He said in view of Mr Letham’s medical condition, he should have been transferred to first class, where sales targets do not apply.
“RMT firmly believes that Charlie Letham was deliberately targeted and the CRISP procedure (Catering Retail Improvement Sales Programme) was used to dismiss him,” said Mr Hogg.
A CrossCountry spokesman said: “We are disappointed the RMT has chosen to ballot their CrossCountry members at Edinburgh. Mr Letham’s position has been carefully considered, including an extensive review with RMT representatives that looked at all the facts together with his medical and personal circumstances. “Unfortunately, his work as part of our catering sales team has been consistently and considerably below that of his colleagues over a long period and falls short of the service we want to offer our customers.”
A final appeal in Mr Letham’s case was due to be considered on Monday, but the RMT said management had cancelled the meeting at the last minute without explanation.