[ido]

    Even if you saved that 100-150 euro every month, 
    you'd not afford buying it after 30 years, assuming 
    it stayed at the same price-point.

The thing is that many people don't have an extra 150 euros per month (not to mention ~50k euros for the down payment) to save or invest in a mortgage, they spend everything they earn every month even when renting.

If you're in a position where you have extra money and you can choose whether to invest it in the stock-market, buy a nice car, or put a down-payment+mortgage on a place to live it's a different consideration.

[pkolaczk]

This is the point I was making: renting is the only choice if you can't get a safe mortgage with good terms. And getting a mortgage with monthly payment X, when you could hardly pay more than X would be a very risky option and even if some (crazy) bank agreed to it, they would set a very high interest rate for covering the risk. But getting a mortgage with a monthly payment X when you can really afford 4X is a totally different story.