To put 5% in more extreme terms: would you play Russian roulette with a 20 chamber revolver and one bullet?
Each interaction for police is like pulling the trigger in that hypothetical game of Russian roulette. This is why the absolute numbers are actually very important.
Well, no. 5% of interactions is frequent, especially for police. They need to be prepared for violent situations. That's a pretty core part of the job.
We can talk about deadly weapons being unnecessary for dealing with violent situations but your quoted numbers just don't support the conclusion you seem to be drawing.