So you're saying house builders are free to get carpenters through H-1B?
There's no reason why not. They'd just have to figure out how to satisfy the rather vague requirements of high skill. They'd have to be pretty highly skilled just to justify the effort, though, since it costs several thousand dollars to get a potential employee through the H1-B process.
How can a person ever chose a profession if the most lucrative ones will just have a back door opened to relieve the price pressure?
Just accept that you're competing on a global market. If someone in India, or Romania, or Brazil, or wherever can do my job for less money, I see no reason why they shouldn't do it. I have some enormous inbuilt advantages in my understanding of the culture and language, my access to high quality education, etc., and if I can't leverage all of those to outcompete them, I deserve to lose. Yes, this means Americans can't just coast on their luck at being born here. Boo hoo.
My opinion is that we shouldn't have an H1-B program, instead we should allow anyone who wants to work in the US to do so. If that creates a larger influx than we can manage then we can be selective but we should still take every highly-skilled and highly-educated worker we possibly can. Brain drain the whole world, because that will keep the innovation and progress here, and keep our economy the most powerful in the world. Immigration has always been the engine that drives economic growth in the US. That was true when my ancestors arrived in the early 19th century, it was true when we used all the Nazi rocket scientists to win the space race, and it's true today.