Your points are just beautiful. Someone talking in business mode (patio11), versus someone in product mode (edv519).
I think your argument is rather about your goals. patio11 wants to make money first of all. edv519 wants to make the user happy first of all. Both views have pros and cons, and you will probably both reach your goals.
You don't understand what Patio11 is saying. He wants to know that your product can actually get people to pay up. It's the ultimate in product validation. Until people will pull out that wallet and sign on the dotted line, you don't know that your product solves a real problem.
That's what Patio11 wants. He doesn't want to get paid up front and he's not in "business mode". He's trying to validate his product in the best possible way.
That's just it. Human beings often say one thing and mean another. Users' willingness - even eagerness - to pay is the one true, OBJECTIVE measure of the value they place on your product.
When people value something, they WANT to exchange money. Why? Because they want to take possession of it.
Exchanging money for value on a deep, primal level satisfies this urge.
Not only that, often times people say they want a solution but it's not what they really want. And often times, people are clueless.
But when they exchange money for value, you have a clear indication of just that - what they value.
I would hesitate to actually get paid up front unless you really do have something coming soon, but it's quite trivial with many of the payment networks to collect the information and not charge until you're ready. If you truly have no product yet and your ability to deliver is not certain, this seems like a reasonable way to get promises to pay for something while still having a way to exit gracefully if you find you can't deliver.
Actually, with Stripe and Amazon they will just hold on to the information and not authorize/charge so you can wait much longer (like Kickstarter). The downside is that you aren't guaranteed to be able to charge the amount at the end, but I don't think that's likely to account for the majority of your customers.
Integrity is assured if you are up front with people.
This is the concept of early customers as stakeholders.
You can be upfront with people by saying, "Hey, I've looked into your needs and painful problems and I really want to serve you. I want to build this solution. But it costs money. Here's an example (show mark up) of what I have in mind. If I get x number of people to buy now, I'll build it. You can even get lifetime access (or some substantially reduced price) for taken on the risk and believing in me".
I think all those people who discount this method of serving customers are letting their fear of rejection get hold of them.
It's okay!
Fear is a natural reaction of the lizard brain; there's nothing to be afraid of.
But those of us that have tried this method and have seen how willing people are to work with you to build a solution (if your "heart" is in the right place, i.e. to serve them), know it works.
Seth Godin has a talk about "shipping on time" and just getting it out there to let the market decide (that's totally worth seeing).
And a lot of software that is already paid for is never delivered. Or delivered late. Or delivered, but not as expected.
Don't. Do. This.
Please don't mix the popular memes of "Release early, release often" and "Good enough" with "Get paid up front".
This happens so often that I've made a career from cleaning up the mess left by people who didn't deliver what was already paid for.
Be very careful if you do this. It's a whole lot easier to repair your code than to repair your reputation.