(1) The “value” of what you buy has obviously got nothing to do with the RRP. It’s a real shame for those that buy at, or near, RRP because they lose out on resale value (not that I think purchases should be made with resale value in mind)
(2) For much of the stuff OO/PX sell, they are the only available source. They are their own importer and no one else in the UK sells it. To mark something as having an RRP and then to immediately start selling it at less than that in a sale (yes, they do this) must fall foul of advertising standards – those ones that say an item must have been sold previously at full price. It’s aimed at the gullible and has been outlawed in most retails sectors.
Provided they have PROOF of it having sold at full price, they’re in the clear. When I worked in the ecommerce voucher sector, this was the way companies inflated their RRPs for Groupon etc to “discount”. Sell 5 in 5 different transactions to staff on their own credit cards (delivery notes to home address) and then you have your proof.
I’m not saying O-O/PX are doing that, but the fact is the law is completely powerless to stop those kind of practices as they left it wide open for circumnavigation, so even if people complained to either the ASA or Trading Standards, there’s nothing can be done.