Some practitioners are self-initiated, and don't follow a strict tradition. Younger members might infer, as you did imply, that only the traditions of which you speak, are valid.
Initiation (both the big I and little i) are relevant to the discussion.
Myself, I performed a magical act without the realisation it was a magical act, applied focus, thought and study and was then "pushed from behind" - I was initiated. No coven, just a covenant.
I Subsequently dedicated myself to a year and a day and haven't looked back since. It remains the most defining moment of my life - it echoes ... it changed the game.
But it was a blessing; I couldn't force it, even now I wouldn't know how - the right alchemical elements were present at the right time to turn lead to gold. A goddess called beautiful serendippity.
Yet people who choose the witches path, who initiate themselves and dedicate themselves to it by choice and belief rather then those Initiated who walk in "faith"? I wish them every blessing. Doesnt your heart flares when you encounter each new seeker - they are taking destiny into their own hands ... besides it could be the path to a deeper Initiation?
Sure they could fail, could walk away - any of us could - but todays failures are simply the lessons for tommorow's victories.
It's hard to make rigid judgements because the world shifts and evolves; the source defies them every time.