This is Jonathan Strange, it would totally kill him to wait. Still, somehow he manages, looking at Lambert's chemistry set-up (though not touching anything) as Lambert puts the coat and boots on. Once Lambert's even more bundled up, Strange walks over to the door and pushes it open. He's the more mobile one, he's the one who'll get doors and pick up dropped things and all that nonsense.

"So, have you even been able to look around at the shopping market in the first place?" Strange has: it's an ample distraction when he's getting nowhere with any sort of stone magic. And he's already spotted a few books he's going to buy for himself. But, he knows he's a lot more mobile than Lambert as is, so he suspects the answer is 'probably not.'