Why do some model coach and wagon kits still use plastic wheels?

With so many kits of railway coaches and wagons out there for consumers to choose from, why do so many still come with plastic wheels?

It's no secret that metal wheels are favoured by many modellers these days, and it can be disappointing when an otherwise great kit turns up with the plastic type included.

But far from being a ploy to annoy their customers, it's likely many kit manufacturers are simply playing to the masses, with more modellers than less either not concerned about metal wheels or have their own ideas regarding upgrades.

Another possibility is that a kit may simply be of old tooling. Many kits on the market today were designed decades ago before metal wheels were as common or desired. To change that now or source outside components may affect the competitiveness of a product or even render it commercially unviable, and a kit with a few old fashioned parts is better than no kit at all!