Autotools for these pretty simple things is an okay approach, but then people tend to go overboard, and that's when it gets horrible (or autoconf itself breaks libxnet detection cause it gets some quoting or who knows what wrong in some release). My personal pet peeve is people detecting endian in obtuse ways that totally fails during cross-compiling when there's the perfectly fine ntoh family.
You don't need autotools, but autotools is the consistent way to do it; the "installed base" is large enough that any sysadmin knows how to deal with autotools (and will have to for many years). Writing your own custom check, even if that check is much more concise in and of itself, makes it harder for a sysadmin to understand your project build than just doing the same thing as every other project.
