The truth is a road and cross bike aren't all that different. The road bike will generally handle a little bit better and be a small amount faster; the cross bike can mount wider tires, and is likely to be set up so you can mount more stuff on the frame. Most people would be fine doing most riding on either.

I had a CX bike for years, and did 50+ mile weekend rides on it. The particular road bike I'm riding now is lighter, handles better, climbs better, etc. But it's a kick ass road bike and was a mediocre cross bike.

I don't think a CX bike is necessarily better for commuting. Honestly I prefer commuting on a road bike, it's a little quicker and less effort. But I don't carry much stuff with me. And on that note, lots of road bikes can have racks mounted to them, it's mostly just the race bikes that can't.

I used to ride over the Golden Gate Bridge and into the Headlands, but I stayed on the roads when I did it. If I needed a bike and didn't plan to leave the pavement, I'd probably get a road bike.