Guides in Morocco are almost all enormously agreeable, but almost always are involved in compensation from the places they take you, and stores they recommend. You might as well accept it; it's the way of the culture. There are some things you can do to protect yourself and keep things moving on a guide and tour level.

If you're heading into the desert for a camel trek, note that the vast majority of camelmen (that is, the men who pack your camels, walk you into the dunes, then cook and drum for you at night) do not receive compensation from the hotels/auberges where they "work".  This is the unfortunate situation of young men in Morocco -- there is so little to do that many are willing to work for free, in exchange for meeting tourists from around the world, being exposed to new cultures and languages, etc.  Hotels/auberges get away with it because they know know these camel men are a 'dime a dozen'.  Please always make sure to compensate your camelmen at the end of the trip, through a cash tip (approx 50 dirhams/5euros) or by purchasing a fossil from them.