When somebody sits on
something or lays on
something they would be testing the comfort, so comfy testers are
people who go round trying to find what is comfiest.
They would compare answers with one another to hear each others opinions on the level of comfyness.
Things that aren't comfy such as a thorn bush would get about a 1 out of 10 but things such as memory foam mattress would get roughly a 9, 10 if extreme comfort is found.