What exactly do you mean by "stick out"? If you mean projecting horizontally from your body like a superzoom does, then you'll find that they don't do that. SLR lenses are so much heavier than the camera that they point down when the camera is hanging from the strap. Even a superzoom with a teleconverter tends to do that.
With a very heavy lens you'd attach the strap to the lens foot instead of the camera, which would make it hang more horizontally, but still not perpendicularly to your body.
I tend to wear the strap over my left shoulder, with the camera on my right hip. That means the weight is on my shoulder rather than my neck. When I need to shoot, I slip my right elbow back through the strap so the camera is hanging from my neck. You need a longish strap to be able to do this.
If the path is narrow I can move the camera around a bit more so it's behind me rather than beside me.
Some people hang it straight down from their shoulder, but I feel like it could easily slip off like that. I found a page showing the three ways to hang it:
http://www.diyphotography.net/the-diy-r-strap
That's a fairly short lens by birding standards, but it still hangs down.