I know it seems a bit of a cheek, but I don't really understand why you're all getting so hot under the collar about it?
Aside from any copyright infingement of using the same photos (which would be wrong if they ARE Argos's) this is not illegal, and I would question why some of you think this is a rip off or immoral??
This is how 'markets' (of any kind) work - based on what a seller is willing to sell an item for, and a buyer is willing to pay. Mostly items do not have a 'single fixed price' or indeed an exact 'value'. There's an old adage, "price is what you pay, value is what you get".
So what if, for example, someone who doesn't live near, or visit an Argos, sees this on eBay, buys it for £100, has it delivered and then loves it, and feels that s/he has had good value out of the purchase - what's wrong with that? To some extent the fact that it is available from Argos for £30 cheaper is irrelevant.
Another thought - perhaps this guy ISN'T buying from Argos and selling on? Perhaps he is just buying from the same manufacturer or wholesaler, and the reason the pictures are the same is because they are provided by the manufacturer/supplier (it's quite common).
This is what makes Ebay work - everyone's willingness to decide for themselves what value (and therefore maximum bid) they are willing to attach to something they want. (In economic terms, it's what's called a 'perfect market' )
Take the example of the next jeans for £15 when for sale in shop for £8... the 'cost' to an individual to buy them at that price might be greater than £15..
Jeans cost: £8
Petrol & parkign to get to shop: £3
Time spent - 1 hour - nominal value: £5
I know there ARE real scams on eBAy, where sellers try to trick or deceive buyers, but I really don't think you can argue this is one...