Marketing is empathy
Communicating successfully and efficiently with someone who might be interested in your product means empathising with who they are, what they want and what they need, right now.
Your language should reflect the relationship with the person you're writing to.
“Dear Sir/Madam” and “Hi Julie” are two ways of interacting with your audience. One of them might be better for you than the other.
The people who designed this gate display at Schiphol Airport do not empathise with their users, otherwise the weather in Xiamen wouldn't take up far more space than the flight destination and number.
If you think this is nitpicking: the chap behind me at the airport was at the wrong gate. You know those “Would passenger XYZ please come to the gate” announcements? Well here's one reason they happen.
Talk to Amlot about empathy.