Thanks Moosegun!
I realised if I scroll down on one of the tabs on a guest, I can see the whole itinerary they have followed so far! Often there are two food shops or two drink shops listed in a row, revealing they wanted a hotdog but settled for pizza nearby because the hotdog queue is basically always full. (Must build more hotdog shops!) Browsing this has revealed that certain food and drink shops are much more desirable than others, which just pick up overflow.
In my park my guests seemed voracious for coffee (like real life, except at 40 degrees Celsius, wow.) I built four adjacent coffee shops to keep up with demand. The way the guests decide where to queue makes total sense to my software developer brain, but no sense at all to my human brain. They tend to all line up at the same coffee shop until that queue is full, and then the overflow gradually fills up the second queue, and only then does the third, and then the fourth, shop receive any business at all. Anybody who's ever been in a grocery store is left scratching their head, lol.
Separately, another question about habitats. If I have 2+ habitats containing the same animal (like for breeding purposes), will the guests attempt to visit both habitats, or will just one habitat cover the wish? (Are the guests aiming to look at a species or look at a habitat?) Eventually I'll figure this out by looking at the itineraries (like above). But it occurred to me that the answer could lead to very different choices about pathing, zoo layout, and attention to scenery.