I can recommend going by this road along the coast if you aim for the south(Essaouira). It's a little slower then the highway probably, but it is a beatiful landscape and you get picked up pretty quickly by locals only. People took me for just a few kilometers everytime, but i think it's way more fun and it really was worth it. Also if your late on time or tired, you can get taxis from every bigger city for 30dihram maximum. Try it!!
Didnt work out for me, in summer, mostly family cars go through here. A lot of cars though, so probably could catch a ride if i stood there for little bit longer. Ended up going by bus to Marrakesh (60dihrams only!!)
Probably not the best spot in summer, since spanish people dont go to work as often, but I got pretty lucky and a guy gave me a ride to gasstation before Tarragona. If you get somehow here, you will probably catch a ride. The spot is after a roundabout, so there is time for drivers to see you. A lot of police patrol, so cant recommend going closer to the highway
Actually good spot. Its not great for cars to stop here, but a huge truck didnt care and very kind german guy took me. I recommend to go to the big gas-station with mcdonalds if you want to go further in Swizz direction, bcs there arent many spots to be anymore in this direction