The name is branding. It ought to appeal to the most people while giving a sense of what the site is about.
How can the amount of money paid be correlated with this?
Say 70 people spend $1 each for one name = $70
While 30 people each pay $3 for another = $90…
You will go for the second name, despite the other being more than twice as popular. Good luck with your marketing on that basis!