I don't want to shop among your garbage.
Just because every store now has a coffee shop in it, and just because they are kind enough to let you drink and eat while you shop, doesn't mean the store is your personal dumpster.
Throw your effing garbage OUT. Find a trash can. I promise you there are about five by the doors, two near the bathrooms, one behind every cashier station, and, oh yeah, about three in that coffee shop where you purchased your now-garbage.
I don't buy that everyone is this "forgetful." Try "lazy." Resist the urge to be a lazy-ass, and carry your disgusting, used, ful-of-your-germs beverage cup a whopping two feet, and throw it out. Thank you.