To comment on what should have been the original point of the opening post - it would be good to find out if this was a sort of spot check by Liverpool or not. I'm not against it if it's random. If someone is asked these sort of questions and says a payment of above face value etc or can't get purchasing details correct (so they don't personally know who sold them the ticket) then it's right that these people and the tickets they have (and who they go back to) should be looked into further.
It's obvious from those that have frequented these forums for over 10 years that Tiger Tony is a regular match goer. It's extremely unlikely that he would have bought a touted ticket. I can empathise with him just wanting to get into an away ground and have a pint, rather than answer some questions about a ticket - especially because at Shrewsbury I wasn't drinking and just stood in front of my seat for 35 minutes in the freezing cold - I could have answered those questions and wouldn't really have been inconvenienced like he was. If it's not connected at all to the previous incident, then it doesn't appear on the face of it to be harassment like stated. But if this is to happen for a selection of tickets at other games going forward, I don't think it's such a bad thing - if some people reveal through answering questions that they likely bought the ticket at above face value that there can be an investigation into how that came about.
Edit: Unfortunately at this stage, we only have Tiger Tony's account so no idea really to know if it was an organised spot check on a random selection - or it was just something to do with the tickets or the reader itself.