I've had 2 BMWs so I should know this....I think technically they don't, but if you get one at a dealership they always have them. There are all-season ones that are available as an option or aftermarket purchase.
I don't think it is "Standard" yet as most low priced base cars the mats are still optional.
A cheaper alternative to BMW branded floor mats is to simply by unbranded floor mats at a local store or car dealership. Floor mats for cars can also be find online for cheap prices.
One can purchase floor mats for cars from any IKEA local store. One can also purchase floor mat for cars from websites like Amazon, eBay, Auto Anything, Sears and Walmart.
Not all vehicles are sold with floor mats. It usually depends on the dealership/person you purchase the vehicle from.
Uline, Mat Depot, American Floor Mats, Office Furniture Mall, and Chair Mat USA offer high standard quality chair mats. Most of these chair mats come with a lifetime guarantee.
The two main fabrics used for car floor mats are carpet and rubber. Rubber floor mats, although not as pleasing to the eye, come in a variety of styles and are usually suitable for all seasons. One can find rubber floor mats that catch and hold snow and dirt or that are customized with a favorite cartoon character, for example. Carpet floor mats look nicer, but tend to stain in the winter and hold water, that if left wet will leave a musty smell in the car.
carpet and vynal flooring
A great place for floor mats is an autoparts store like NAPA or autoway. However, if you want to save a lot of money, you can check a place like walmart and even places like Big Lots and Ross sell floor mats for cars for very cheap.
Most of used car dealers throw them away. There are other more environmentally friendly ways to dispose of used car floor mats.The carpeting and rubber backing from the mats are excellent insulators. Used car floor mats could be used in the attic of a home to improve insulation.I have seen car floor mats cut into sections and used a knee protectors for gardening or construction work.Used car floor mats can also be placed on the floor of the garage to absorb leaks and spills underneath the car.
American Floor Mats and Mats for Less offer customizable floor mats for every possible vehicle. You can also make inquiries at your local auto supplier.
Cadillac car mats can be purchased when you go to a store called CariD. This store sells auto accessories like car floor mats for many brands and makes of cars, Cadillac included.
I am not sure if the BMW Z3 comes with a standard retaining post. If there is a retaining post in the floor, you should absolutely use it. If there is no retaining post, you will get excellent traction on most floor mats with the non-slip backing they are produced with.