A reviewer pointed out that the laces actually work.  They do tighten up the wide heels nicely.

These slippers walk comfortably.
The wide toe area is comfortable.
The footbed is the cushiest I've ever experienced.
The soles are solid.
My feet are WARM.  Finally.
They slip on and off easily, but they don't fall off or slip when I'm walking.  This comes from adjusting the laces.
The inside fleece shapes to the foot and then holds on, rather than being too crushingly tight.

Higher sides for ankle warmth would be a plus, but those cost more than twice as much.  Maybe next year.