Why do the henna ladies grab your hand?

Once it's on, you're expected to pay — typically 300 to 500 dirhams for a small dribble, a price that's never mentioned beforehand. Hands in pockets or visibly occupied reads as unavailable.

The ink used by street henna artists is low quality and stains everything it touches — textiles, towels, bed linen. If you wipe your hands on your riad's towels, the stain is permanent. Henna ink cannot be washed out of fabric.

Professional henna is a different thing. Most riads arrange sessions with actual artists — agreed design, agreed price, usually 150–200 dirhams per hand, with proper quality ink.