This is a special type of policy exercised by some door lock manufacturers. They allow the copying of their keys only in certain places having the appropriate equipment. The purpose of this measure is to lower the risk of people getting duplicate keys without the permission of the property owner.
If you trust your neighbor enough to give him your house keys, that is great. It will be very helpful in the case of a house lockout. Although this is a practical solution, it's not often recommended especially if you are not sure about your neighbor or who has access to his home.
It all depends on one simple thing; maintenance. Proper maintenance of locking mechanisms can ensure that they last as long as they possibly can, and this includes proper use of keys as well. For example, Locksmith Montclair experts suggest never slamming keys into the cylinder.
The simple answer is yes, conventional locks are just as useful now as they were back then. It all depends on your discretion and how many locks you put on a single door. While high-tech locking mechanisms can be tempting, they are also quite expensive.