> the advantage of using multiple mints is lower probability of rugs

Why? 

I get the part that only 20% of your nuts got stolen if you have 5 mints and 1 of them rugs. 
But what do you do after that happens? 
Add a new commodity mint that can do the same exact thing?   
Add 10 more mints you don't know anything about?
Spend significant time comparing and picking mints, that all are still incentivized to rug you? 

Who does any of that after being robbed?