In NL, Dag has a lot of meanings concerning greetings, so yeah, it's accepted.
Is this a common expression? Since dag can mean both hello and goodbye, I could see this getting confusing.
'Dag' is a very common expression for saying both bye and hello.
This shouldn't get too confusing. At the beginning of a conversation you say 'hi', and at the end of a conversation you say 'bye'.... ;)
"You say yes, I say no. You say stop. And I say go, go, go... Oh no! You say goodbye, and I say hello! Hello, hello! I don't know why you say goodbye, I say hello!"
Je zegt ja, ik zeg nee. Je zegt stop. En ik zeg gaan, gaan, gaan…Oh nee! Je zegt tot ziens en ik zeg hallo! Hallo, hallo! Ik weet niet waarom je tot ziens zegt, ik zeg hallo!
What about "hello and have a good day"? Or is it said in a different way?
I would say that "have a good day" is quite more formal than "dag", a simple and succinct way of saying bye. :)
Some ways of saying bye are more formal than others.
- Tot ziens
- Vaarwel (like 'farewell')
At first, i thought it was 'hello and hello' cause dag can mean hello too
Whenever there are these funny absurd sentences I always take a look at the comment section to have a laugh :D