I like the show, it shows how to do things in the ideal situation. Although it's rare that an ideal situation every exist.
Now with saying that contractors face a lot of issues with home owners on doing things the best way possible. Most home owners usually want things done the cheapest way possible, a lot(not all) only see dollar signs. So now a contractor that would do the best job and use the best materials available comes along and gives you a quote for 50,000 for a garage. Then the next contractor comes along and says he can do it for 25,000 dollars. 99% of all home owners would go with the cheaper contractor thinking a garage is a garage. Contractor 1 might use 2x6 studs spaced closer, better wall sheathing, better vapor barrier, thicker cement for floor, rebar, trusses rated for higher snow loads, 50 year roof shingles, more nails on the shingles, better siding, etc. Then contractor number 2 shows up and gives his low bid because he is only using 2x4 studs, spaced 24" apart, thinner sheathing, thinner concrete, no rebar, 15 year roof shingles, etc. Both of them can get a garage up and it will probably look alright but which one is better quality and will last longer?
Things that home owners can't see can add up quick, ice and water shield on the roof, proper weather sealing around the windows, rebar in concrete, quality of shingles, etc. A typical home owner will see a garage floor, weather there is rebar in it or not and that floor will probably hold a vehicle just fine. But if you drive a heavy truck in there or after years it will start to crack.
So the quality contractors that would like to do their job with the best materials and the best work and charge for it have to compete against hacks that come in at half the price. Some home owners do realise quality work and materials and are willing to pay the extra when you sit down and talk to them about the benefits of everything. Some aren't, all the see is the price and saving money. Now the biggest problem is the homeowners that expect the best garage for the cheapest price. They don't understand how one guy only charges half the price of the other.
One poster above stated how home owners have to baby sit contractors and tell the contractor exactly what to do since he is paying the bill. This just means he has never worked with a quality contractor before. You should not have to baby sit a quality contractor. The problem is when home owners hire the cheapest guy and expect a perfect job, this is where he has to babysit the contractor.
Bottom line when hiring a contractor is 99% of the time you get what you pay for. Don't expect the best job if you don't go with an experienced contractor and pay for that experience and quality. If you hire the cheapest contractor then expect the cheapest work.