Dunkin unveils new 'nighttime' beverage

American adults may not agree on politics or social issues, but one thing they do tend to agree on is that it's hard to make it through the day without a good cup of coffee.

Of course, within the realm of coffee, consumers certainly show loyalty to their favorite chains.

Related: Forget Starbucks, another coffee giant promises higher prices

In many parts of the country, you're either a Dunkin' fan or a Starbucks fan.

Sure, you can be a regular at both. But due to the cost of buying coffee versus making it at home, many consumers like to commit to one chain over another so they can benefit from its rewards program.