Money in Morocco

Get your local Moroccan dirhams from an ATM once you get there. Don’t bring cash with you to Morocco (unless you have a desert tour company that wants to be paid in U.S. dollars, like ours did), and use dirhams once you get there.

I was there in January. I hadn't realized the dirham is "protected", as I prefer to have about $100 in local dollars prior to arrival anywhere outside the US. I'm in the minority with this! I also know fees are higher but purchased some at the airport from an agency vs an ATM. Some hotels and restaurants appeared to also accept USD or euros.
I was with a group of 12 on a tour. The guide was helpful along the way with stopping at ATMs she knew reliably worked- even still, sometimes some in the group had their cards rejected. Cash was often needed in smaller towns and rural areas, depending on your itinerary.
(You're going to need cash/coins for toilets, every- where!)
It's a fascinating and beautiful country, have a wonderful trip!

You can't get or spend dirhams outside of Morocco. Get some from an ATM at your port of entry, and reload as required. ATM's are everywhere, but some are finicky. Using euros will cost you a lot in hidden exchange rates. Its always cheaper to use the local currency. Just think: in your hometown, would YOU rather be paid in Euros, or in your local currency?

Ditto the need for coins. You will need them for bathrooms, tips and many purchases.

THANKS for all the advice

Beware, and this may have changed since I was there, but there were no currency exchange places behind security in the airport in Casablanca. I didn’t know this and got stuck with a bunch of dirhams as I wasn’t going back through security again.