Assuming you’re paying out of your own pocket, I can say from experience that the lawyer/accountant/other professional service ilk are just as likely to baulk at the additional £226. To earn that back in 3 hours, you need to be earning £128k per annum after tax. While there are accountants and lawyers et al who earn north of £300k, they are few and far between.
Remember when there was all the fuss other news about the top 5% of earners earning £80k per annum? A day’s work for them is £300 before tax, so roughly £200 after tax and pension costs. Even then it’s a case of asking if you’re happy to spend a day’s salary for a couple of hours on the train.
Repeat: First class train fares for business travel are paid for by the employer, not the employee.
Hourly wages and hourly rates are not the same thing. Employees get paid a salary which works out as £X per hour. The employer actually charges a multiple of X to the client to cover overheads, profit, eyc.
And for a first class fare the employer probably charges it to the client, where a first class fare basically amounts to a rounding error in the overall fee.