I remove pins when they're right in front of the foot, or sometimes already under the foot but before they get to the needle. By that time there's not much left to slip. Besides eliminating the risk of hitting a pin, it also means that when I'm done sewing I don't have any stray pins left in that I haven't noticed.
Sometimes when I don't pin but need to keep seams aligned, I just pinch it with my fingers until I get to that spot. When the fabric is really bulky, the pin itself can warp it, and pinching it works better for me.
Fabric clips might be something to consider. I have some and use them occasionally, and they work pretty good for some things.