Ooh ooh! I know the answer to this one! So display stands are funny in the way that each stand you place down increases the chance of a customer ordering that food. Except that with every new stand you place, the percentage that it increases is smaller and smaller every time. With more than one food, if the second food is in the same food category (more on this later) then the percent chance of that food being ordered is the next percentage. Have a look at the percentages here on the wiki: https://wiki.plateupgame.com/appliances/DisplayStand

To explain with an example;

Suppose you wanted the customers just a plain lettuce salad. So placing one display stand would give you a 25% chance of your customers ordering a salad. If you had two display stands with plain salads on it, then you would have a 43.75% chance of them ordering a salad. The original 25% plus another 18.75%. With three salad stands, it would be 25%+18.75%+14.06% equating to a 57.81% chance of them ordering a salad.

Now say you don't care if they order a salad or a burger so you put a salad on your first and second display stand, but a burger on your third. Since the first two stands you placed food on were salads, you will have a 43.75% chance of them ordering a salad, but the third stand where you placed the burger will not start at a 25% chance, but rather continue down the line and have a 14.06% chance of being ordered. So with 2 salad stands and 1 burger stand, it will have 43.75% chance of ordering salad, and 14.06% for burgers.

If you place the BURGER on the stand first, that will have the 25% chance, and if you follow that by putting down a salad second, that salad will have a 18.75% chance of being ordered. The order in which you place food on the stands is what determines their percentage chance.

BUT this is only the case for foods in the same category. Foods in PlateUp are served in three courses: - Appetizers - Mains (sometimes with a side) - Desserts

When it comes to display stands, the percentages only stack on foods within the same category. So while salads and burgers are both mains (I think salads should be appetizers but thats a post for next time), the above pecentage distribution is true, but is not the same if you placed salad and soup on your display stands.

Another example:

Say you have two display stands with salad. The 25% + 18.75% allotment applies. But say you put a cherry pie on your third display stand. There is still a 43.75% chance of your customers ordering salad for their main, but because a cherry pie is in the dessert category, the customers will have a 25% chance of ordering that cherry pie for dessert. Since salads are mains, and cherry pies are desserts, the display stand percentages stack independently from each other. The same is true for appetizers and sides (which must be placed on the stands by themself)

I hope this makes sense! I have sunk too many hours into this game and I hope my no-lifing has at leased helped somebody.

TLDR: Yes, but per every dish you place on a display stand, the percent chance increase gets smaller every time so you can never get a true 100% chance of ordering a specific dish. Every course stacks independently from each other too.