^^ What Scotty says!
If you check the "body only" price vs. the "kit" price which includes the 24-105 f/4L IS... and note the difference. THEN check the price of the 24-105 on it's own, and you'll see it's a MUCH better deal to buy the "kit" version of the camera.
There are a lot of people who will buy a "body only" camera but the retailer only has the "kit" in stock. So they remove the lens, "white box" it (put it in a plain box because they don't have the retail packaging as it came in a kit with a camera) and sell those new lenses on their own so they can sell the body to the buyer who wanted a "body only".
The white box lens wont be as good of a deal as if you had just bought the lens as a "kit" package with the camera, but it'll still be a lot less expensive than buy the 24-105 f/4L at retail.
Also, check the used market for lenses.. From my experience this is a great alternative and I've hadd good epxerience with this. I've had my reservations before but I realized lenses are just optics, no need to wait for technical helpdesk to answer you if something goes wrong. Like with the camera, which I advise buying new.
Another thing is that most people that spend big bucks on lenses tend to be professionals, so they take good care of the lenses. After all lenses are quite expensive new, and stay expensive, but do drop down in price if you're to get them second hand.
[Mod note: Removed link per FORUM GUIDELINES.]
"... tend to be professionals, so they take good care of the lenses."
You jest? That is not my experience in the least. Pros tend to 'use' their gear. You would be shocked by what I have seen some "professionals" do to their lenses.
The best person to find is someone that buys 'bling". Some guy that is a techno freak and has to have the latest greatest and rarely uses it. The guy that loves hanging a 1Dx around his neck and only know the P mdoe. They are out there.
I just got the 6d. What is a great all around lens to begin shooting with?
Depending on where you bought it, you can return it for a refund. Then you could re-purchase the Camera with the kit lens for a saving. I've done it, when I took the item back within the 30 day refund period.