That mostly says something about the socio-economic status of the people commenting in here, going to any big Walmart-like store in the Western world most of the bikes for sale there are still made of steel, not of aluminium or other light materials. I'm talking about basic bicycles like this one [1] (I had one from the same bike manufactured), they're made out of steel.
How certain are you that bike is made of steel? That sort of flat and fat tubing is typical of aluminium, since it is a weaker material than steel in terms of cross-sectional area.
They have been shaping cheap steel bikes like that for years to make them look like aluminum. Some of the buyers aren't even looking for an aluminum bike, they just want a 'bicycle' that looks modern. It's a pity because it means the bike is much heavier than it would be if it had nice slim steel tubes.
Any discount store bicycles in Australia are made in China and all have aluminium alloy frames from what I have seen. (Most are of a mountain bike or BMX style)
If you walk into a high end bike shop you won't see many steel bikes, you'll see them mostly with higher end materials like aluminum, titanium, or carbon fiber.
Most people aren't getting their bikes from a high end bike shop though, most are getting their bikes from discount shops like Walmart, which sells mostly steel bikes.
