In the glory days of McDonald's, Ronald rung in the holidays usually with some sort of great Happy Meal promotion. The most famous McD's Halloween promotion would the the various trick or treat pails that were practically an annual tradition. For a few years tacking their commercials onto the 'Scared Silly' spot was another tradition as you'll find various editions paired with that classic bit.
While the obvious intention was to use these trick or treating, they usually became various storage containers. Crayons and other school supplies were a popular use. McGoblin was home to many a Battle Beast in his day in my bedroom. They had a lot of uses, except for actual trick or treating as they were pretty small.
My cousin generally used them along with his sisters. I'll never forget the Halloween where he was VERY jealous of my Paas make up kit werewolf costume. Dude was a bed sheet ghost with some cold cream on his face. Not even Kooky Spooks and a robe as the official Halloween costume. His McBoo pail got hard spiked into somebodies yard during a temper tantrum after the third time tripping over that sheet.