The 'fat tax' is real. Here are 5 examples that prove it's more expensive to be plus-sized.

"Fitting into the flying sardine cans that we now call airplanes is difficult at the best of times," said Carrie A. Trey of the The Points Guy, "add to the equation the fact that the seats are designed for one specific body type that's not at all representative of everyone who makes up the 'flying public.'"

The post lists 12 different airlines and their "passenger of size" policies. Alaska Airlines requires passengers to pay for an extra seat if they "cannot comfortably fit within one seat with the armrests in the down position." United Airlines states that, "A customer flying in the economy cabin who is not able to safely and comfortably fit in a single seat is required to purchase an additional seat for each leg of their itinerary."

Finding budget-friendly furniture that accommodates a plus-sized frame can be a challenge.

The cheapest patio chairs sold on Home Depot and Target's websites support a weight of up to 250 lbs. With the average American man weighing nearly 200 lbs., according to the Centers for Disease Control and Prevention, many in the plus-size community likely surpass the 250 lbs. mark, forcing them to buy more expensive furniture.

Mattresses, too, are not always made with the plus-size community in mind. People "don't even realize that the average mattress is designed for someone who is 250 pounds," said Dalessandro.

Among Business Insider's best ranked mattresses, though the Lucid memory foam mattress was ranked best affordable mattress, heavyweight users who tested it gave the latter some of its lowest scores, meaning for a good night's sleep, they likely would have to invest in a more expensive mattress.

"Biking while fat" can also get expensive. The cheapest bike on Bicycling magazine's list of the 14 best cheap bikes for every kind of ride costs $134.99. The cheapest bike on the magazine's list of best gear for big riders, specifically, is $910. New York City's bike sharing program Citi Bike has also come under fire as its bikes don't support a weight of more than 260 lbs.

In the '80s, Keith and Julane Davis started casket-making company Goliath Casket. They've since seen the demand for larger caskets grow.

''People are getting wider and they're getting thicker,'' Mrs. Davis told The New York Times in 2003.

Titan, which sells caskets at retailers like Walmart and Amazon, lists the starting price for its caskets on its own website at $999, with the oversize caskets starting at $1,499.

• Read more:
• Walmart has acquired plus-size fashion brand Eloquii for a reported $100 million — here are 20 of our favorite styles
• Christian Siriano said he tripled his business by including 'plus-size' clothing — and it makes no sense that other designers aren't following suit
• Four former Gilt executives just launched an online shopping emporium dedicated to the plus-size fashion market
• Kmart has renamed its 'plus-size' section in stores — but people think its new name is 'patronizing'