have no idea how people manage to break them off inside of guns, but I wouldn't imagine removing them is much different from pushing a cleaning rod or a dowel down the barrel to force it out.
You apparently haven't read the various threads about trying to remove one. The boresnake is soft, and it tends to expand and grip the bore as you try to force it out. Anything you use to drive it out has to be stiff enough to resist bending and soft enough to not damage the bore. (The example picture shows how many soft rods were required to drive one out. Switch to a new one when it bends and try again...)
If you are lucky, you will never have to experience this. However, there is enough history on these things, which do
not involve misuse, that I threw all of mine in the trash and went back to a cleaning rod.
If you need a portable cleaning method, you can get sectional rifle cleaning rods which break down to 8 inches, vinyl-coated for those who worry about the joints having sharp edges, which will fit in any shooting bag or hunting pack.
(As an aside, I consider bore snakes somewhat similar to a wood stove. I know the darn thing is hot, because there is a thermometer mounted on it. I have yet to succumb to the desire to place my hand on it to verify that it is hot. So, the fact that a boresnake
can break off and ruin my day is enough for me to condemn the design. I have no need to experience it.
)