PLAs lower melting point is the issue. I only print PLA, mainly because it's less toxic, but I dare not print a part that might end up in a hot car, near a heating source or outside.
Same. 95% of my prints are PLA, but I've had PLA prints deform in my trunk on a hot day. For more durable prints, though, I prefer PETG over ABS for its lower shrinkage, better plate adhesion, and lower fumes. ABS is just generally not a good thing to print with.
See here [1]. No FDM printed item is going to be food safe because the layered properties allow the accumulation of bacteria, but PLA is generally non-toxic and will only leach a few "safe in small quantities" chemicals into things it comes in contact with.
Could they mean that the material is suitable per 21CFR, but as you state, it would not meet the cleaning requirements. Benign material that could be single use, but a user should not be expected to be able to maintain a clean surface?
I think that's it. Ok for single use or for things that will only come in contact with food that will be cooked (like cookie cutters). Not ok for plates, cups, spatulas, etc. unless you seal them post-print with a food safe coating. I've seen people print both categories of things, though...
As for toys, I don't see a big problem. Even if you eat PLA it won't really do much harm. It's safer than the ABS most toys are made from.
https://box3d.eu/3d-printing-safety-pollution-health/
From this one data point, it seems that ABS is the big emitter.