I can count on one hand the number of "benign" leaks that I've seen over time.
So the answer is a very qualified yes.
An example. If you have a singleton resource that needs a buffer to store a circular queue or deque but doesn't know how big the buffer will need to be and can't afford the overhead of locking or every reader, then allocating an exponentially doubling buffer but not freeing the old ones will leak a bounded amount of memory per queue/deque. The benefit for these is they speed up every access dramatically and can change the asymptotics of multiprocessor solutions by never risking contention for a lock.
I've seen this approach used to great benefit for things with very clearly fixed counts such as per-CPU work-stealing deques, and to a much lesser degree in the buffer used to hold the singleton /proc/self/maps state in Hans Boehm's conservative garbage collector for C/C++, which is used to detect the root sets, etc.
While technically a leak, both of these cases are bounded in size and in the growable circular work stealing deque case there is a huge performance win in exchange for a bounded factor of 2 increase in the memory usage for the queues.
