I agree there are more complications than my analogies suggested. But nothing a little programming could not handle. Some sites don’t have a problem and have allowed selection successfully for years even with manual systems.
I don't see it as in anyway a software issue, just a fundamental one as Tobes in # 74 well illustrates.
If a desired pitch is not available for the entirety of a requested booking, that request can't be granted. Client needs to modify their requirements to fit what is available or walk away.
This failing to secure that booking leaves the site exposed to there being a booking, or a more flexible client coming along that does fit in the hole(s).
If so great, if not that pitch has days of no occupancy.
Clearly it is a business model choice sites can make, take possible hits to plicate the specific desire of some clients, or go down a route with less risk of vacant pitches. It's a balancing act the site operator chooses their preferred model.
I suspect the CMC prefer to chase the higher general membership occupancy model, than being "nice" to individuals.
We have been affected, being able to use one pitch for a few days, up till a particular date, and move the lot, full awning etc to another pitch for "X" days, only able to stay anywhere on that site up to another date.
If there were an abundance of people willing to move pitches and accept a limited stay, then that helps the site, but I sense we are not thick on the ground. We only did so as we were meeting friends, so dates and location had to match.