That's precisely it: for developing 32 bit applications.
As it stands, I have many computers that could benefit from me programming a 32 bit application, but only my rpi could benefit (and my cell phone, I suppose) with the ARM builds.
32 bit is also helpful for me because I have some 32-bit IDE (like the naobot from Aldebaran IDE). It is simply easier for me to develop and configure.
You want to develop 32 bit applications? Well I would imagine you would want to develop them for (and why not on) the most widely used 32 bit ISA out there... ARM. ARM has had a 32-bit ISA and hardware using it since 1995, and is now moving to 64-bit with Aarch64. Thankfully, they are doing it a hell of a lot better than how Intel managed the transition back in ~2004-2006 with x86-64, even though they are almost 10 years late to the party. But by all means ARM is 32 bit.
Obviously you meant x86 every time you said 32 bit in your reply. While it is pretty pointless to get into a religious war over processor architectures, I think it should be noted that the base compiling tools such as GCC and now more advanced/cutting edge ones like LLVM/Clang have started to give developers platform independence with cross compiling. As long as the libraries used have support for whatever you want to compile to (and almost all current packages and major libraries have ARM support), you can cross compile to x86 and vice versa. While I'm not a Stallman level FOSS advocate, I do love the fact that having as many open components to software allows this application portability to be a lot easier.
Both Intel and ARM can work well in 32-bit, I don't see your point. On the contrary, if you're so hung up on the word size of your processor, ARM is a better fit than x86, since the latter is often running a 64-bit OS these days.
As it stands, I have many computers that could benefit from me programming a 32 bit application, but only my rpi could benefit (and my cell phone, I suppose) with the ARM builds.
32 bit is also helpful for me because I have some 32-bit IDE (like the naobot from Aldebaran IDE). It is simply easier for me to develop and configure.