As to the matter of price, most of my wine tasting friends (including some with proper wine collections) are perfectly ok paying 5-10 euros for a bottle, as long as they like the wine - some of them have even made it a specialty to find good and cheap wine.

At the other end, I was once served wine without knowing what it was at a friend's place. I took a sip, then something happened in my head, and I started crying (I cry when food is really good) . I still remember that particular bottle, and the, well, infinite landscape that had suddenly opened in my mind (I know it sounds utterly ridiculous , but this is how it felt). No other wine has had the same effect on me, and it turns out the bottle was worth about 400 euros!