It's not so much about showing them traveling, but about the viewer having some idea where each character is and where they are going. We see Jorah at Old Town and when he's cured he says he will return to Daenerys, so it's not jarring when he shows up there. This episode, Jon makes a plan to get to Eastwatch, we see him set off and then arrive there. We don't see either of them travelling but we know where they are going so when they arrive, it's expected.
When Euron shows up out of the blue not once but twice, it's jarring.