If thats true, then it would be a really myopic policy by Samsung. Customer who uses their < 3k mobile today may well buy their premium handsets tomorrow. He may even be using the < 3 k mobile as a 2nd phone or for his parents or grandparents, etc. And after experiencing their service, he may well put off buying any Samsung mobile in future.
Samsung gotta be real dumb if they are really practicing such discrimination.
As for the handsets, having used a ~ 3 k Sammy briefly, few months ago, I was not a satisfied user. Wasn't much satisfactory in either signal strength or keyboard or anything else... not even considering the price. I'd say Nokia is better here. But then it does depend on the particular model more than just the brand.