Your took my comment in the other topic a little out of context, but I'll bite on this anyway.
What I said was most customers have more budget than they let on.
To answer your question, yes often they are crappy salesmen. That's not meant to sound demeaning, but they are your words--not mine.
A salesman's job is to fit the right product to the customer's budget. Sometimes that is Chinese cameras, but often it doesn't have to be. Most salesmen (in any industry) are not very effective.
Customers walk into a sale with a perceived budget. This is what they are willing to cut a check for without ever hearing what you have to offer. If they've bought cameras before, you may be lucky. Often, it's a baseless amount or a comparison to something they can buy at Wal-Mart. When the salesman presents the quote, it's their job to educate the client both on the merits of the product, and about the price. You have to make the client see the value of the product you are offering. Once they understand its value, their perceived budget will become more in line with the actual cost. You've convinced them what it's worth. Making the sale is now just a decision about whether or not the funds are available. More often than not, people are willing to spend more than they initially thought they would have.
Most salesmen I've encountered do not follow this approach and they run into the problems you are describing. In my opinion, they are not good salesmen. They are simply presenting quotes and waiting for approvals. They are not "selling" anything.
When determining what your customer needs, you have to determine whether their budget represents available funds or whether it's simply what they are willing to spend. In nearly every single case it will be the latter. Don't offer an inferior product or leave money on the table if you don't have to. On the few occasions where there really is a hard line budget, then what kind of budget system you offer is up to you.