It happens all the time. As an automotive technician, I've had to beat on tires with a sledgehammer many times in order to get aluminum alloy wheels to break free from the steel hub. And just recently I purchased an aluminum bike with an aluminum seat post. The seat post wasn't stuck in the seat tube and came out easily, but it did have a bit of surface corrosion on it. I buffed it off with a wire brush and wiped a thin layer of grease on it before putting it back in.