I agree with others that this is not discrimination, it’s business. This issue comes up time and time again. Dealers get a handling fee (around £230) per Motability car plus the order counts towards their manufacturer, group and dealer based bonus targets (which can be significant). In-stock cars have already counted towards all of those targets, so a Motability deal is worth just the handling fee to them, versus potentially a few grand profit if sold to a private customer.
Dealers, like many businesses in the current climate, are trying to survive in a pandemic where they have lost a fortune and just when the rest of the world is recovering they are hit by a semiconductor crisis that will cost them sales for another year. A Motability customer walking in is an opportunity to generate another new car order, with all that entails. They will therefore want to place a factory order to help with their targets.
It is sometimes possible to secure an in-stock car for a Motability customer if the dealer knows that it won’t shift it quickly, has several of them or needs to make space for newer stock due in, so it’s always worth asking, but it’s wrong to criticise a dealer who has the option to make either £230 or £2,300 from the same car depending on which customer they sell it to!