Some background information.

Megatrain offers tickets on normal scheduled trains run by SW Trains but only certain times and certain routes. Their T&Cs specifically say you must use the right trains and go to the right places.

These people wanted to go from A to B but really wanted to go to C which is a stop between A & B.

They broke their contract so they were fined.

If they wanted to go to C then they should have bought tickets from A to C or went to B then paid for another ticket from B to C.

In this case trains from Southampton to Eastleigh take 11 minutes and cost £3.20 if bought just before travel.