Take a look inside Menards, the Midwest home-improvement chain owned by Wisconsin's richest billionaire

Menard Jr. is the 89th richest person in the world, Forbes reported.

After spending a summer constructing pole buildings to put himself through college at the University of Wisconsin—Eau Claire, he started a construction company in 1958, according to Menards' official website. That led him to the building-materials business, and he opened the first Menards retail location in 1964.

Now with over 300 locations across 15 Midwestern states, the chain sells a wide variety of home-improvement tools and building materials as well as appliances, lighting, furniture, and groceries.

Menard Jr. is a controversial figure known for his frugality and iron-handed management style. A 2007 Milwaukee magazine profile reported that managers are fined $100 for every minute a store opens late, and Forbes reports that even top executives are still required to clock in.

In 1997, Menard Jr. was fined over $1.5 million and pleaded no contest to charges regarding illegal hazardous waste disposal. Prosecutors alleged he used his personal pickup truck to take dangerous chemicals from the business to deposit them in his household trash, the Milwaukee Journal Sentinel reported. Menards paid another $2 million in 2005 for violating state water-pollution laws in Wisconsin.

His personal conduct has also come under scrutiny with a 2013 lawsuit alleging he pressured the wife of one of his business partners to have sex with him and fired her husband when she refused. Menard Jr. denied any inappropriate conduct, his attorney told the Milwaukee Journal Sentinel.

Menard Jr. is also an avid race-car enthusiast, sponsoring Menards race cars at NASCAR and IndyCar events.

The Menards store I visited in Milwaukee's Northridge neighborhood spans a whopping 162,300 square feet, the Milwaukee Journal Sentinel reported.

The pickup trucks cost $18.95 for the first 75 minutes, $6 for each additional 15 minutes, and 50 cents for each mile driven, according to the Menards website.

Most stores I visit in the Midwest don't have extensive security measures. When I compared shopping at Target in New York City and Wisconsin, I found the New York location featured "secured shelves" and locked cases, while even limited-supply items were kept on open shelves in the Midwest.

Menard Jr. is known to be serious about anti-theft measures. He set a policy that store managers cannot build their own houses to prevent them from stealing supplies, Milwaukee magazine reported.

The aisles seemed to go on forever.

Menards didn't have a produce section, but it did have a refrigerated section with gallons of milk and frozen food.

For example, a family-size box of Honey Bunches of Oats cost $4.93 at Menards. At Metro Market, a Midwestern grocery chain, the same box cost $6.29. I see why my dad swears by it.

Oreos were created as an imitation of Hydrox cookies but eventually superseded them in popularity, making Hydrox look like the knockoff. I'd never even heard of Hydrox cookies until I saw them at Menards.

The root beer was labeled as the official craft soda of the Automobile Racing Club of America's Menards Series. A 24-pack cost $19.99.

Menard Jr.'s son, Paul Menard, raced in the NASCAR Cup Series.

The items also featured QR codes to scan for online shopping.

Unlike other home-improvement stores like Home Depot and Lowe's, Menards doesn't offer installation services. Instead, it directs customers to local service providers so the store doesn't act as a competitor to the contractors who shop there.

Milwaukee magazine reported that Menard Jr. used to recycle wood scraps and heat stores with the leftovers.

The section also included grills, gazebos, and swing sets.

The gardening section sold potted plants as well as seeds, soil, outdoor decor, and gardening tools.

The section featured Mike Lindell's MyPillow, Ped Egg callus removers, and portable handheld fans, among other items.

I could see how Menards, a family-owned Midwestern brand, would inspire the kind of loyalty that would make people want to wear its hats.

On the day I visited, Menards was offering an 11% rebate in the form of a merchandise credit check if you mailed in a receipt and a completed form. The rebate percentage fluctuates, but the system is a hallmark of the Menards shopping experience and helps keep its prices even lower.

Even long after I left the store, I couldn't get the "Save big money at Menards" jingle out of my head.