100 C has no practical application for most values of real life.
You don't boil water by setting something to 100 C (or 212F for that matter). You turn up the dial to medium-high and wait for bubbles. Or stick it in the microwave for some number of minutes.
0 C also not so practical. My refrigerator's freezer compartment lets me choose on a scale not related to C or F. In any case, it's a temperature below freezing.
Not to say metric is without merit, but it's practical applications are not a good argument for people familiar with imperial units.