The person who needs a predictable routine is not necessarily resisting adventure.

Predictability is often what makes everything else possible. Someone who keeps the same bedtime, the same route or the same Sunday is usually not afraid of novelty. They are managing energy, health or a mind that works better with fewer open questions. The steady frame is what leaves room for the interesting parts.

Before you tease someone about being set in their ways, ask what the routine does for them. Plan the spontaneous thing around their fixed points rather than through them. You will find most people are far more adventurous when the ground under them is not being moved at the same time.