I think it's just a bit of a defeatist attitude. Don't try, it's too hard, build a lego building block robot instead. How are people going to learn without doing. Robots are a great problem solving exercise, its not helpful to anyone to be told to give up and do something else when they ask the best way to do something.

Its not like making wheels like this is the height of difficulty either. I did this as a 13/14 year old (Not wonderful quality granted) with the bare minimum of kit.

Personally I'd go for the bearingboys wheels. They're decent enough and are uk based + cheap.