First of all, we don't caulk much of anything except where a countertop meets a wall. That's painter's work. No, they don't hire scabs. The hall sends guys that aren't working and pays them a pittance for showing up. Everyone is obligated to participate twice year, working or not. Sorry to hear about your experience with the bad. The UBC training is second to none. Everything from door hardware certification, solid surface fabrication and installation, OSHA 10 & 30, Rigging, fall protection, confined space, lead paint, Scaffold, and a number of other certifications you can't get anywhere else in one place. Try not to confuse trade unions with industrial unions. Different animals.