This is a false equivalency. Putting on a seatbelt poses no danger and requires no effort. Giving police military-grade vehicles and weapons, on the other hand, costs money and isn't safe, considering their track record.
a) whether they are edge cases, which they are in terms of occurrence b) risk, which are comparable on a personal level
Additionally, when seat belt laws were introduced there were arguments about whether it was a moral hazard. Their requiring some effort (try strapping in a small child) and considerable danger to some (again, children, and pregnant women) was not relevant to that (ultimately wrong) argument and it's not relevant here either.