I agree with all the possibilities above, and have also thought some were preforms, others like it was said before were no longer utilitarian, Also as for the lousy looks of some, like it was said, if it would cut, and would fit a shaft, be it an arrow, or atlatl, or whatever, it was used. as for beautiful work, look at ishi's work, and others, and then come south, and look at the unbelievable work, or coral, and chert, like the Newnans, and Hillsboro's, and other styles. Plus there was a lot of trading going on. Look at the Folsums, or the other fluted point that I can't think of at the moment. They were thought for many years to only be a lower western style, and not destributed anywhere else, till they were found on the east coast, down about four to six feet in river banks, and washouts. Also I think a lot of the ugly ones were either unfinished, or made by beginners, and or kids. The way my stuff looks, they could have been made by some of my ancestors.
As yet, I am unable to make pretty, but I can make functional, which is what the main goal is when you are after something to eat. Look at some od the flakes we get when we are spalling, some of them would take very little to be fundtional with any flaking at all. I personally think that they did have some liesure time. Once you got food, and shelter, you pretty much had all the bases covered, till the food started getting low.
Anywho, that is my dollar two fifty's worth of opinion, there are just too many varying situations, in which some of the points that are found, got where they are, and in the condition they were in.
Wayne