Marriage Doesn't Give You Every Right

Even though Nathan and I are supposed to be one unit, it turns out there are some things we can't do for each other. When Nathan received a check from his grandma for his birthday, he gave it to me to take care of. I had him sign the back of it and then took it to the bank to cash it. After handing the check to the teller, she asked,

"Who's Nathan?"
"That's my husband."
"Okay, well he would need to come in to be able to cash it."
"Really? Even though we're on the same account?"
"Uh-huh."
"Uh...can I just deposit then?"
"Sure!"

I realize policies are policies, but I was still caught off guard. All I have to do to take money out of our account is fill out a withdrawal slip; I've never even been asked for an ID. But cashing a check made out to my husband? Apparently that's stealing.

Have you run into any surprises about what you can't do for your spouse?