It has happened to me a few times, and one of them I can share.

When I was negotiating for a new job, it was all email, until I asked whether it'll always be work from home (this was during the pandemic). Instead of an email reply, I get a call and the HR tells me it should be work from home always.

Fast forward, the pandemic is "over" and people are now being called over to work. My contract is worded ambiguously enough for the company to defend this "order". I realise if the earlier conversation was an email, I would have a case for myself that I never agreed to this (not that I would go the judicial route, but still).