Well, I think it's unfortunate that all opinion polls work that way. A small sample size can skew results in one direction. The objective is to get to a sample size as large as possible. I hope this goes in that direction.
A few months ago i painstakingly submitted a product of mine to many places listed here. It was 100% ignored while many sites asked me to pay a price so they can post about my site. The general modus operandi is to claim "we get lots of submissions. We can move you up the queue list if you pay $$$."
I agree these sites need the revenue. Just don't claim to be torch bearers for the startup community. Be upfront like ProductHunt which says pay us to get promoted. No harm in that.
India has an often criticized reservation system where 50-60% of seats in colleges/universities are allotted to people from lower castes. This puts enormous pressure on economically backward kids from upper castes who have to score upwards of 98% to get admitted whereas a person from a lower caste can get admitted by scoring just about 50%.