**TL;DR:** Physical locks are simpler and therefore less prone to failure. Proximity cards (e.g. RFID) are superior in every other way.

**Picking a lock**  
 is a side-channel attack that grants access to an individual who does not need to have ever encountered a valid access token (in this case, a key). It's quick, highly effective, and leaves no audit logs (other than perhaps scratches). Nearly all locks are vulnerable to picking to some degree.  
**Picking an RFID station**  
 would be a similar side-channel attack against the station hardware itself or against the underlying protocol. No such generalized attack exists, but specialized attacks against specific hardware may be possible. 

**Cloning a physical key**  
requires only a photograph of the key and the appropriate key-cutting hardware. Commercially produced hardware for doing this is available at minimal cost, or you can do it manually using a file and a decent ruler. The distance at which you can clone a key is unlimited for practical purposes, and requires only line-of-sight. Whether or not sufficient resolution exists to do this from space is not publicly disclosed, but it may be a possibility. A cloned key can be made indistinguishable from an original. In some cases it's also possible to use the physical properties of the lock to create a working key (without ever seeing another "real" key). Every key can be cloned. Without exception.   
**Cloning an RFID token**  
requires a device to read and reproduce the RFID signal, such as the Proxmark3. This is a specialized device which is readily available but not widely possessed. Higher-security challenge-response tokens cannot be cloned by reading their signal. Full stop.  

**Revoking access for a physical key**  
involves re-keying all the locks so that the revoked key no longer works. Simply returning the key is insufficient, as keys are trivial to clone... even if they say "do not duplicate".  
**Revoking access for an RFID key**  
involves telling the system to stop trusting the revoked key. No further work necessary.