Brothers mate used to do this kind of thing for a while, earnings weren't too bad, but he did used to moan about the amount of hours he had to put in.
As MooMoo points out, Van rental costs these days are pretty extortionate, so being cheaper than them helps, but most of the work he got was word of mouth.
So yeah, maybe something you could do for a short while, but can't imagine many wanting to continue on for many years.