It is understood that most of these men are former steel workers, so the choice of the abandoned factories as a practice facility is certainly not accidental: the filmmakers clearly meant for this to be both symbolic and comical. The "Steel Strippers" find work once again in the steel refineries; since there is no longer any steel, they work with what little they have available to them -- their own bodies. Specifically what makes the situation in "The Full Monty" so funny is that it is so pathetic. One of the right wing objections to the welfare state was that it created a class of individuals who fed off of the scraps of society, and had no motivation or desire to contribute to the world in any meaningful way. "The Full Monty" portrays, by contrast, a group of individuals dying to work, in any way possible, but still...

The structures formerly in place to provide them with employment no longer exist, and those aimed to help them in times of need are slowly being pulled away. Their situations are pathetic, so their grand scheme to acquire money, to be amusing, must be equally pathetic.
Also noteworthy is the fact that while there is no longer any business for steel in Sheffield, the sex industry is booming. The utter decline of this community is exemplified by the fact that the most profitable activity is not productive in any way; the "Steel Strippers" can only find work in the service sector. "The Full Monty," in many ways, is intended to be an answer to the opponents of governmental support for the poor. It presents a group of men with virtually nothing to offer, who offer absolutely everything they have.