Social Justice... Does it really mean the lazy never have to work again?

[Duke Malcolm]

Well, like I said, a class system is a bad idea

And while designer clothes and McMeals are not a good thing, nobody is forcing the masses to buy them (yet).

To get back on topic a bit, that's part of what social justice is, the upper class gets a whole lot of benefits for being born to the right people, without deserving it. Social justice is making sure the lower classes get what they need to live a decent, human-wordy live, and making sure (as much as it is possible) they get their chance in life, and can live up to their potential.

Hardly. The upper-class only get benefits becauset they have worked for those benefits. They invest in their children, send them to a better school, a public school, thence University. Admittedly, there is a problem with University fees, something that should be tackled by increasing the number of people available for bursaries and such, not showering the poor with money. If you give a lower-class person £10000 much of it would generally become disposable income : if you give a middle-class person £10000 much of it would generally be put aside for better things - university and school and such : If you give an upper-class person £10000 much of it would generally be invested in some way.

Edit:
Economically, a sensible person does not try to eliminate the classes through redistribution of the wealth -- each person would use the money in such a way that would rebuild the classes.
A sensible person does try and increase social mobility through the classes -- more University grants as long as admission requirements are equal for all; more public school grants; improving school funding instead of giving less well-off children money through the EMA...