A big thing as well is how trained up certain TOC staff are
For example at TPE guards cannot Penalty Fare anyone, or even issue a UFN (Unpaid Fares Notice). Only revenue protection can do these. But we can report them for prosecution, and after 1y competency as a guard, we can directly issue a TIR (Travel Irregularity Report) to them, without having to go "via the back office"
Contrast that to LNER, where TMs can issue UFNs, or Northern, where guards can PF people - to my knowledge at least
This is a big problem IMO as it means there will always be different outcomes - if someone comes across a TPE guard they'll probably just get sold a new ticket, but if they came across a TPE RPO or they were doing the exact same journey on a Northern service (York - Leeds fx), they'd probably get penalty fared. If they made the same journey on LNER (York - Newcastle fx), they would probably get a UFN. Three different possible outcomes all for the same "crime" of not having a valid ticket, all with varying severities and impacts - £20 for a new ticket, £50/100 PF + £20 new ticket, or reported for prosecution (potentially offered a £150+ settlement) and given a criminal record...