First we must separate the locals from merchants.
The merchants of course are the people who sell you products or help you for a fee. These individuals may be friendly, but of course, they have an agenda, which is ultimately to sell you their product. Many often end up trying to pressure you until you buy something. Their friendliness has a purpose other than just being friendly.
But we are not really talking about those people. What about the people in the streets, at the squares, at the restaurants, and on the trains and buses? Yes, the Moroccan people are very friendly. Some people proactively will offer you 'salaams' and ask you how you are (Labas?!).
Some will make conversation with you, asking you if it's your first time in Morocco, and if you're enjoying it and where you have been. Strangers often told me 'marhaba' meaning 'Welcome (to Morocco)'. My conversations have mainly been in the little French that I know. Some know a little English, but you don't often come across people that know English unless they've studied abroad.
When I've taken my many train rides there, people have helped me with my heavy luggage on and off the train, and with identifying my stops. When I got lost, young boys recruited the help of others (above photo) to figure out my way back to my riad and even walked me back without expecting a payment at times. When I was lost, some even called their friends and family asking for help with directions so that they could instruct me.
I've been to East Asia, the Caribbean and South America where the environment can be harsh, but one thing I have discovered is that 1. The friendliness of the people can make all of the difference as to how you perceive the country and 2. Your openness and friendliness with locals will also make all the difference in the richness of your experience.
Feel free to smile with people and say Salaam (peace/hello) and 'Labas?' (Are you good?!/How are you?).