Setup fees do not need to be refunded even if you offer 30 M.B.G... if its stated in your TOS.
Its a great way to deter frauds and 'host hopers', which are simply testing out different hosts, or are trying out a host for their host review site, or whatever.
Setup fees are also a good way to attract REAL customers. Anyone who knows anything, will know if the price and service is good, then you dont mind paying a small, one time setup fee... right?
Would you pay a setup fee? You would if you were serious about your hosting.
I am totally
for setup fees, as you can probably tell