I don't think bikes with lugged frames count as being gas pipe. And any bike with aluminum crank arms or rims is definitely not a low-end bike.
The common bikes sold by retailers in the 60s/70s, at department and hardware stores to people who wanted to spend the least money, did not have lugged frames and had hardly any alloy parts at all, and they weighed 35-40 pounds.
A lugged frame bike may have straight-gauge tubing, but it is thinner wall than the tubing used on bikes that did not use lugs such as the Huffy, AMF , Columbia and low-end Schwinn bikes. The low-end Schwinn's were real anchors, but they were usually more expensive than the other USA made bikes, so a lot of blue-collar kids did not get them.
My parents bought me a Columbia 10-speed back in the 70s and it had no frame lugs of course, and it had almost no alloy components at all that I can remember, usually only the stem and some shifting components might be alloy on these bikes, but not all of them. I can't remember what happened to my Columbia after I totaled it out in a bad wreck around 1979 where I smashed my face into the pavement and got amnesia for a while. The bike was scrapped for sure, but I don't remember how, usually I can remember stuff like that. There was a pond back in the woods that most metal scrap ended up in, good chance it is in there.
Anyway, a few years ago I bought this 1973 Huffy because it was my size and the same quality as my old Columbia, and I have put over 3000 miles on it since then, most of this forum are familiar with it. It is a very fast well sorted bike, not the best handling, but good enough;
