Without seeing this particular demonstration, it's hard to judge. I think £450 is an absolutely ridiculous amount of money to spend on something as mundane as a hairdryer, and even if I could comfortably afford to buy it, I wouldn't. There are obviously people out there who would consider it worth spending that sort of money, or have so much disposable cash that it takes no more consideration than throwing a tin of beans into a supermarket trolley. However extortionate the price is, it's part of their product range - and they need to, and have every right to try and sell it to us. They don't need to consider those in financial dire straits, why would they? If the demo actively encourages people to go without essentials in order to pay for it, then yes, that's shameless and insulting. Talking about "easy pay" instalments = fine, just so long as they're not making crass comments such as "Nobody will notice a little £100 going out of their bank account for a few months" or " Do your shopping in Lidl for a few months and go back to Waitrose when it's all paid off"!
They will always be luxury and overpriced goods and people who can afford to buy them, or are happy to spend the extra cash, just as there will always be people struggling to provide their families with the most basic of needs. It's a horrible imbalance I know - It would be good to see Q do what TJC do - raise money to provide meals for hungry kids!