Why is libgtk deb under main/g and not under main/libg? (?OT)

[Shriramana Sharma]

I had to manually download libgtk, libatk and libpango for some
reasons. So I searched the pool for libgtk under libg, but it is not
there. Similarly libatk and libpango are not under liba and libp. They
are under main/g/, main/a/ and main/p/ respectively.

But libcairo is placed under libc and not under c.

I do not understand why this disparate situation is. When is a libx*
package put under libx/ and when under x/ ?

Thanks.

P.S: Apologies for slight OT nature of question but I thought only
developers can answer this so I asked here.