Why hasn't someone invented

Why hasn't someone invented

• milk jugs that get smaller as you use the milk so they take up less room in the refrigerator?
• chocolate chip, coconut, and nut bags that have zipper tops?
  
• pickup trucks with adjustable beds so you can change the size when carrying larger items or smaller items?
• chips made from eggplant or zucchini?
• a pretty coffee mug that keeps your coffee hot?
• a fitted sheet that won't pop off the corner of the bed when you roll over?
• a bed that tilts up for making it when it's positioned against a wall or in a corner?

What can you think of that you wish someone would invent?