That's not because we don't find it useful, we just have local alternatives.
for living room furniture... Most of it is from IKEA
Amazon often does NOT tell you the shipping costs until just before you make the order. This while any other price comparison site allows you to compare prices including shipping (e.g. Tweakers.net pricewatch). I don't understand why people use Amazon. From my colleagues only foreigners use Amazon. Dutch colleagues often use sites which might be foreign, but at least appear more Dutch.
German Amazon uses machine translation for appearing to be Dutch. Original language is German. Another bit which makes the experience annoying.
Lastly, most Dutch sites offer really easy returns. Amazon is more of a hassle.
I always see in the product page an info saying "THIS SELLER DOES NOT DELIVER TO IRELAND"
That isn't to say you would want it over the alternatives if you had it. I personally almost never use amazon. I know people who get something delivered every few days. Different people are different.
If Amazon _did_ turn up, would it have an effect? Probably. Would it be game and/or life changing? Unlikely, since these capabilities are already available in here.
You are correct that we are not used to getting everything from the same vendor. But it is absolutely common for people to order stuff online. Our "high streets" are just as empty as those in the rest of the world.
And yet I have not found a convenient online store that has even close to as much as Amazon and is competitively priced. If I want to buy a monitor what is there? All the domestic dealers are beyond awful, and I can use overclockers (a UK site) but the shipping is high and soon I may have to pay tariffs too. I go to German, Spanish sites too now and then but even if they have what I want it's generally overpriced and shipping is quite expensive. I also need to go to 6 different places if I want 6 different things, so I can't combine shipping. If the EU wants greater union it might be worth making it as cheap to ship something from Dublin to Tallinn as from Boston to San Diego.
Though tbf I have been moving towards using more ebay, or dealextreme when I can (and am ok with waiting 6 weeks).
They already paid big chunks of the bills for Ireland's roads, ports and airports. Asking them to subsidise everyone's postal costs too is a bit much.