First Class is actually much BETTER value in many businesses.
Say you're a client and you want an adviser/consultant etc to attend a meeting. That consultant is charging your company £500 per hour.
If it's 6 hours travelling time in total then that's £3,000 to pay for them to sit on their backside doing **** all...unless they can guarantee that they will be able to do some other work and therefore not need to charge you travel time.
Generally, the only way you can get into a position where you can definitely get work done is travelling in first. So for a £500 quid ticket you avoid £3,000 in travel time costs.
Also, if you travel regularly, it's almost impossible to keep up with work unless you can make good use of travel time. I go through periods where i'm flying twice a week, or catching long trains. that's too much dead time, completely not workable to be sat doing nothing.