I don't get it.
I use Trainline to check fares, My first question is: does the fare change each time you go back on the site, like say, Ryanair's do as the cookie tells them you're interested, so the price goes up? Or, once published, are they 'fixed'?
We normally book a day or so beforehand (it's for a DC at a nearish uni to come home for weekends if he wants). The earliest train we'd look at is 8pm on Friday, sometimes late morning Saturday, then back to uni 8pm on Monday.
But the fares can be £2.40 one way, to £12.40 one way. But even then, it'll go 9am train £2.40, then hourly- £2.40, £9,35, £2.40, £7.22.
None of these journey could really be considered rush hour!
What algorithm is at work?
It's not as if anyone browses the site and goes "Oh! That trainfare is only £2.40! I'll definitely get that! Even though I have no reason whatsoever to visit that place!'
You don't tend to impulse buy trainfares, do you?
Curious.