This has been a bugbear of mine for a while!
Initially dealers had an excuse as they couldn't distinguish between the two sorts on the Cared4 website.
But now they can distinguish between the two, so they no longer have an excuse...
It's not a trivial detail either!
I find this totally ridiculous. There was the excuse that there is no tick box for flex. That does not wash because some dealers manage to include this vital information either in heading or elsewhere. Reading between the lines as to what is and is not flex I see that ex-demo cars often have only 2k difference in price. Except for the paid ones I buy of course which have been cheaper than many flex offers. Funnily both the ads for my cars did have that vital information. After I had paid a deposit on the clear understanding that the car was batt paid they put me through to the salesman who opened with I will just explain haw your battery lease works: I nearly hit the roof. Other dealers just had me wasting their and my time asking if a cheap deal was flex or not, they all were flex.