Sheetrock installers are very proficient and there are hundreds of tricks of the trade. “Rocking” is almost never an hourly job because the work is so strenuous, your arms are above you head much of the time, which is seriously painful until you get used to it. Sheet-rockers take jobs on a per-foot basis to stay motivated and profit from their proficiency. There is generally a set minimum per foot price that is upheld throughout the regional market to ensure that this proficiency does not become a liability to himself and his vocation.
There is an economic equilibrium that most construction markets will fall into, a certain amount of builders will require a certain amount of completions per year, roughly the same number of homeowners will do additions; therefore, the demand for sheetrock hanging stays relatively static, unless the supply of sheet-rockers increases. An increase in labor supply can be a hardship, but if the market rate is upheld, everyone adjusts their lifestyle accordingly and there is no hard feelings – it’s just a fact of life.
A problem occurs when there is an incursion of foreign-labor, generally illegal labor and therefore indentured, generally having complete disregard for the per-foot minimum status quo. Having no ties to the community, their only interest is improving life for themselves, bringing in more relatives to the US and “buying” into the market with lower per-foot prices.