Yes, because chloramine isn't as powerful a germacide. It is used to stabilize the water once the chlorine has done its job and is generally put into the water by treating chlorinated water with ammonia but not to the extent that all the free chlorine is consumed.
Carbon filters remove chlorine as well as chloramine
C* + HOCl --> CO* + H+ + Cl-
where C* is the active carbon site and CO* is that site after it's been oxidized by the hypochlorite. What's really interesting here to me is that if you look in the chloramine equation C* doesn't appear at all. That is because chloramine can reduce CO* back to C*. If the water contains only chloramine the filter will last forever (it says here) whereas if it contains chlorine as well it will eventually have to be regenerated.
