[CFrance]

I can tell you what happens if you don't ever change the filter... the ice maker will stop working.

We were using a Britta up north for drinking water, so we disregarded changing the filter in our LG French door fridge. After the filter apparently became clogged to capacity from filtering the water going into the ice maker, it simply stopped letting enough water go through, and we were getting a few cubes every couple of days.

I too wonder if the filter can be disabled in modern fridges if you install a whole house filter. For instance, the Whirlpool Gold French Door fridge (2012). I'm sure Whirlpool wouldn't tell me.