Earlier quoted context omitted.
Buying anything above, say, 100€? Smile, say 'discount?' and they will through in something for free or give a few percent off. And that's before any kind of negotiation (unless you count asking nicely as negotiation). And I mean anything. I've done it in many places. Is there anywhere where that does not work?
can you expand on the "anything"? I'm having doubts that I can negotiate the price of eg. a TV bought in a hypermarket (Walmart, to give a US example) ?
You can try asking the next time you buy something big. The worst that can happen is them saying no, if you really asked nicely.
PS: I dented a rental car and got a huge bill. I called them up and basically said 'discount please?' They gave me a 20% discount, and that was without any kind of arguing or confrontational talk, just the question. So it's not just for stores.