10 blocks is very much considered walking distance in NYC. People walk here all the time - it's the default mode of transport to nearby places. Cabs are usually used for specific reasons: transporting something heavy, bad weather, rider has poor mobility (injured leg, etc.), had a lot to drink, entertaining/working with a client, etc.
This isn't true in the rest of the US, however. The rest of the country is less walkable and the infrastructure is designed for cars first and foremost, so people learn to default to cars even for nearby trips. When I lived in California it was hard to get people to walk anywhere, even if it was only 5-10 minutes away.
Then again, the cabs were probably 5+ times cheaper than what I was used to in the UK. Maybe I'd use them more if it cost me $5, not £10 to go around 10 blocks away. One is close to spare change, the other I'd have to think about...