Don't be so naive. People will always be burned by coffee. People who are allergic to nuts will continue to accidentally eat nuts even though it says "warning, contains nuts", people will continue to walk into traffic even though it says "don't walk", and people who buy a hot drink will continue to accidentally spill it on themselves even though it says "warning, hot". Putting labels and warning signs on things doesn't stop things from happening, it absolves those who might be held liable from liability.