Rec 90 is too high an octane. Golf carts should only use 87 octane. Sure they’ll run on 90 octane, but 90 octane burns too slow for cart engines and cart will begin getting sludged up and start back firing after awhile.

Gas for golf cart
 

My cart is 22 years old. I have never used anything but regular 87 octane and have never added anything. The cart runs fine. No mechanical problems.

I’ve had over a dozen boats and I would follow this method:
* use regular gas in your cart
* fill your cart’s tank to max
* if you are leaving for months, add Stabil to your gas then run the cart for a couple miles to run the treated gas thru your gas lines and thru your engine (mandatory to treat your complete system)
* add Heat or Stabil Fast Fix to your cart’s tank that eliminates any moisture buildup in your gas tank
* take out the spark plugs and shoot a couple squirts of oil in the cylinder(s)

I never had any problems with rust/moisture in the tank after 5 months of sitting

Our 2010 Yamaha which has a carburetor, sits May to October. The octane of untreated gas degrades over time. Our routine is:
a few days before leaving fill it with premium gas and add marine grade stabilizer
shut off the valve at the tank
put cart in neutral, start it and run until it stops to remove the gas from the carburetor
Never had a problem except it does take some cranking to start on our return

no one has said anything about top tier gas , most of the cheap gas is not top tier gas. like wawa, Walmart . top tier gas stations will have a big sticker posted on the pump .

No need for that in a golf cart either.

If you follow the tankers they will go from WaWa to "top tier" stations and deliver the same gas. Gas is gas and there is no such thing as top tier except in advertisements.

False.

Gas as I can tell Base stock same, it’s the company additives added. On side of tankers you see long tubes that’s the additive they add when delivered. Who knows where Wawa or circle K buys gas from what company? Some companies claim there additives are better like chevron and shell. I do know chevron fuel injector cleaner rated over all other brands, but have no proof it works any better other than marketing and ratings? A guy on Utube named “Project Farm” does all sorts non bias tests on products I sure he’s covered this subject?

Maybe someone actually worked delivering fuels can post the facts?

Yes, the base is the same. Additives are added to brand specs.
I've found many stations don't charge more for top tier.
Costco also sells top tier.:
Non-biased explanation:
carfax.com