Cheap in a name doesn't suggest people are cheap... It means you are getting a deal on something that would otherwise be costly.. ex Cheapflights...etc. and likewise coupons are not for "cheap products", but for expensive or everyday products that are discounted...Getting 20% off a iphone wouldn't make it a cheap product.They're long shots.
I personally don't like Cheapons.com. Coupons are already known to be for the sake of cheap products; so putting "cheap" in the name doesn't enhance it much by adding any new meaning. And coupon shoppers don't want to think of themselves as cheap, in any case.
CheapGrabs.com is better.
But don't develop based on the domains you buy. Buy domains based on the development projects you're already halfway toward launching.