Ed - you appear to have a case of "my way is the only right way," something that is pretty common in this business. I might even have been accused of that myself.

Just remember that there are others who are just as smart as you, and may have even been doing this a little longer who have different opinions.
Your box analogy is nice, but flawed. When you do a drive by (and like I said earlier, I do very few) you know what the exterior looks like and the type/style of the house. You can see what the yard looks like, and what the neighborhood is like. You can get an idea of the interior from public records (which are good in some areas and less reliable in others...there are areas around here that I would not do an exterior only because the records would be so unreliable, but there are other municipalities where they are always really close). All you have to assume, really, is that these records are correct and that the condition is average. If the house clearly is below average from the street, you do not finish the assignment as is. If it appears to be above average or average, you do the report as if it is just average. You explain that it is based on the assumption that the house is in average condition. And, the few times I have done one, I tend to be a little more conservative than I might if I had seen the inside. Everything you do is explained, and the client understands that these assumptions are all part of the report. If they really cared what the market value was, they would order an interior appraisal. But, since all they want to know is a ball-park estimate as to what the property is worth, they have no interest in bothering their client with a walk-through. And that is the reason for most of these orders, not saving money. I charge the same or slightly less, depending on wher the property is located.
Guess what? When a bank has a client that has a very good credit score, and a lot of equity, they really aren't interested in what you consider to be the only way to get a report done. They are interested in pleasing their good to very good customers. These are not people who they are concerned about foreclosing on, and they are not people with 95% LTV loans. Feel free to take what you consider the high road, and rail against those who actually provide a service for their clients. And do not compare this to number hitting, as they are two entirely different things.
That said, I would rather have trained under a mentor who would not budge on these types of things than one who would please everyone, no matter what.