Many were caught today, even on slower trains like the S8 in Zürich. There was a big force of at least 8 Kontrolles, plain clothed, who suddenly got up and enforced ticket checks, and netted several.
Those caught bought the Anschluss tickets, monthly tickets etc. - good revenue for SBB.
I should have asked him ( the Kontrolle ) if he had a ticket for his SBB bag.