I notice in the December AAIB reports that Tiger Moth G-ACDC (the oldest flying) got a bit bent in a ground collision.
Taxiing down wind, on concrete between parked aircraft (it has a tail skid and no brakes!)
When we flew Tigers taxiing 'off field' was taboo without someone holding each wing tip and even then the CFI got agitated if you taxied even close to anything on the grounds that with 3 people present it was much safer to push it!