Ok, my query rose due to the 32 bit option for Debian and other GNU/Linux distributions, so why not FreeBSD?
If you look the other way, it is a not a good idea to run 64bit OS on anything less then 2GB(or 4GB depending upon support) and have no plan to enlarge the node, so 32 bit still makes sense for some use cases, like a bastion/jump node, a SSH tunnel, storage node, 32bit legacy software, etc.
Off topic, many ARM SoCs in the market are limited to address 2GB, though the processor is 64bit.
Next, thanks to pkgng, people can use binaries instead of having to rebuild everything, this does make sense on small nodes having 4GB or less. Compiling, building software requires time and resources, if you require customization for the software that you use across many such nodes, you can save time by pre compiling and having your own repository. This is really easy on FreeBSD.
Again when you can offer 32bit option to other distributions, why not for FreeBSD?