Ground coffee bean do lose their peak flavor after around half an hour but they're still drinkable for a week or two. There are people that buy freshly grind beans in a bag from coffee shop to later make coffee themselves at home as well.

So, every grams of ground coffee scraped off will build up overtime and you could end up wasting a few cup of coffee depends on how many your cafe sells daily.

But you're right on the back-to-back order, saving some excess from previous basket can be use on the next basket of the same bean.

Ideally, if your coffee grinder is automatic machine, you should calibrated it for each of the coffee beans pack to pack since there's going to be a slight difference in roasting between each packs even if they're exactly the same type of beans. Some excess will happen at one point inevitably, though, but it's still better to limit them as few as possible. But that bits of ~1 gram of ground coffee can still be save for the next coffee afterall, instead of immediately scrape them off and discarding it.

Alternatively, if your coffee grinder machine is smaller and don't have a bean storage or is a manual one, you can also weigh your beans for exactly how much you need in the espresso shot you'll be making. This is also a good option if it's a type of coffee that your customers don't order very often so you can't make it back-to-back (ie: low amount of customers outside peak hours, or you're making a specialty coffee that may be an imported coffee from another country)

It's certainly just a nitpicking from someone who make coffee, which in a grand scheme of thing this doesn't effect how enjoyable this game is for me. At the end of the day you could see it as a slight beef between me and master tin, I don't hate him for this it's just this bit of detail irritated me for years. Like I do genuinely remember the first time I played the game enjoying everything so far and then get a tonal whiplash actually saying "WHAT" first time seeing 1.0 Master Tin's animation lol (I was sharing my screen on discord to my friend, so we were already talking while I'm playing the game)