In the case of scarce goods and services/time, then yes I agree, charge what it's worth within a given market. But V4V has a place. Understanding what it is and where it works requires also understanding what it isn't. One thing it isn't is a donation. Donations are gifts with nothing expected in return. V4V is an alternative approach attempting to monetize infinitely reproducible (aka, non-scarce) digital content. It is a transaction for having received something that added value to your day in some way. It's similar to a tip. There are pros and cons to various approaches -- subscriptions/paywalls vs. V4V vs. ad-supported, and so on -- and I don't think it has to be all or nothing.