I think you went too far with the "prefer it" conclusion. Just because lots of people do something doesn't mean it's proof that they prefer it. They may take the bus because that's what they can afford, whereas they'd prefer to walk or drive or something else if they had the means.

Also, the 25 million figure is number of rides per month, not a measure of people who ride transit. Somebody might ride the bus to work 5 days a week, and that counts as 20 rides. The count of "people" that ride those transit methods drops to well below 1MM, factoring that in.