Apache.org used to have them for 2.2, never for 2.4. The person that made those installers decided he didn't want to anymore.
The install.txt file was probably just modified from 2.2 to 2.4 when the source was branched off from the development tree. At that time no one knew that there wouldn't be any made. So I guess the install.txt file needs to be changed to not say that.
With Windows Vista, program files became protected and creates problems for Apache.
I used the installers for many years back in the 1.3.x days but haven't used one now for years, it's just too easy without the installer to mess with. Sure you could fill in ServerName and ports up front but with these zip files you just drop the Apache24 folder inside them to the C drive (or D:, E:, etc.), what is so difficult?