Seriously, some people like their beef very rare, or blue. I’ve seen TV chefs the Hairy Bikers nibbling raw fillet steak, and when they did cook it, it wasn’t for long.
I love my steak extra rare. But in the US, hamburger or ground meat is often from a much different (and definitely NOT safer) cut than the cut that's used for steaks (sirloin, tenderloin, etc...).
If you went ahead and bought the much higher grade of cut/meat and ground that up (the types of cuts that high-end restaurants that serve steak tartare), you very likely will be fine. But even at higher-end burger restaurants, they are required to give a warning on the possibility of food poisoning for those who order their burgers less than (I think) medium.