APT is supposed to be a replacement for dselect, and not a replacement for dpkg. However, since addition functionality has been required for APT, and given the fact that this is very closely related to dpkg, it is not unreasonable to expect that additional functionality in the underlying dpkg would also be requested.
Deity/dselect are the first introduction that people have to Debian, and unfortunately this first impression contributes greatly to the public perception of the distribution. It is imperative that this be a showcase for Debian, rather than frighten novices away (which has been an accusation often levelled at the current system)