Are we picking on Primark?

Following yesterday's stories about Primark (firstly that they were stocking padded bikini tops for girls as young as seven and then that they had withdrawn them), there is a really interesting (and provocative) piece in today's Guardian's Comment is Free by Laurie Penny. Basically she concludes her piece by saying that the issue of padded bras for pre-teens is not the problem (agreed) and that the problem is a culture of "commodified sexual performance" (also agreed). However, I'm not quite sure where in this argument she somehow manages to justify the wearing of padded bikini tops and berates MumsNet for picking on Primark (as opposed to, say, M&S) because that's where the working class shop. A pity, really, because she makes some good points otherwise.