A few years ago we rented a Kia Soul on a trip. It was the last year of the original design (2013). It was a nice little car, loved the tight U-turns it could make. But a bit tight on luggage space behind the rear seat.
At the first hotel, after I pulled the suitcases etc. out, I thought I'd lift up the floor cover and see what the spare looked like... No spare, and no place to put one! OK, must be undercar... nope! I took the owners manual in to flip through that night, and found there is no spare, but there IS a helpful can of tire sealant
Of course, the tire sealant can was missing from the rental car. Someone told me that it was common for rental companies to pull out all of the easily-pilfered items, that they store them till they sell the cars. Don't know if that is true or not. But that would explain rentals where BOTH sets of keys are on the same key ring, which was made of stout steel, welded at the juncture. So no keys could be separated.
Anyway, I want a with-us spare for any vehicle we own.