Because you need to spend hours painting and labeling a tray in order for guests to know that those are in fact ritz crackers and red grapes. Just make sure they don't eat the chalk! Better label that too, just in case.
I used homemade chalk paint (1 cup latex and 1/4 cup baking soda). The paint color I used is called Posh Red by Valspar and I used a glaze to darken it a little. I added new hardware from Hobby Lobby, distressed along the edges and and sealed with Johnson's Paste Wax.