>>8790494>are they really rugged and reliable or something?Yes, but that's not why they are expensive.
>are they so much $$ because of the machining involved?, less polymer so costs go up??The 1911 is, apart from grips, all steel, and has comparably a lot of parts. For instance, a glock barrel is one piece with no separate barrel bushing, a 1911 is 3 pieces plus a bushing. The glock uses a machined slide and barrel, and the rest of the parts are mostly injection molded plastic and stamped steel, so it's much MUCH cheaper to crank them out.
Now, you can get inexpensive 1911's that use cast frames & slides, and metal injection molded internal parts, and some of them (rock island aka armscor) are considered very high quality. However, if you are a 1911 purist and want every piece down to the grip screw made out of forged dwarven mythril, then expect to pay for it.
The funny thing is, when you consider that a RIA 1911 can be had for around $100 less than a glock, you are getting much more craftsmanship for a lot less money with the RIA.