On a side note, people really need to replace the filters more often. The number of people I have run into who never have replaced any filters in their kitchen disappoints me.
The tap water in my current house is perfectly fine, so why should I even have a filter? My previous house the water wasn't perfectly fine (I forget what was in it, but the lab failed it) so I had a separate filter rated to take out the bad things in my water - again why replace the fridge filter that wasn't as good.
Either replace the filters or use the bypass cartridge. You don't want to leave a filter in forever so you don't get bacteria growing in your drinking water.
Given all the people that don't replace their filters, they're kind of an anti-pattern.
I drink water straight out of my sink. If you live in a developed country that has safe water, why bother with filters?
My wife doesn't like thr taste straight out of the tap, so she uses a Brita filter.
Personally I can't tell the difference, but she swears it's different.