First of all thank you for being sensitive and for respecting the culture.
It is true, that most of the moroccan people don't like to be photographed at all and it is good to respect that. But this doesn't meant that everybody is like that.
If you photograph people from close, yes always ask for permission. When you approach the person, smile and try first (if possible) to engage him/her in a small conversation and then ask for a photo. Accept a 'no' as an answer with a smile. The more you can engage with the people, the more you will be able to get a 'yes'. Some people will ask you for money, that is up to you whether you give them something, but if you give, don't give much (to children it is not good to give money, but small gifts). On the place Djemaa el-Fna in Marrakech you have to pay if you like pictures from the performers (snake charmers and such).
For overall scenes you don't need permission, but still it depends how far away you are from people. If people get annoyed walk away.
After 6 years of photographing professionally in Morocco, I learned that it has a lot to do with yourself and how you approach people. Maybe you will not get so many portraits like in other countries, but those you get will be good memories because you interacted/connected with the people.
Good luck and have a great journey.