LOL!!! Maybe in NYC. But then again, maybe it's a Cali thing? Whenever I've gone in a proper sit down, non takeout, non fast food place, I've never gotten a spoon. I haven't traveled much to the east coast at all.
I do use my chopsticks though. I eat the tofu and seaweed first, then swish around the miso and drink it down.
Oh also when they give you samples of miso soup at the markets, they never have spoons. They just ladle it into a small foam cup and give that to you.