surprises under the kitchen sink

I've had dramas with my apartment ever since I bought the place back in 2005. In fact, it wasn't long after moving in that I first noticed a damp smell coming from the kitchen area. Because it was a new apartment complex, I got the builders to come in to check it out. At the time, they insisted it was just the pipes and that things would settle. It didn't. The skirting board started to expand indicating that there was a moisture problem under the kitchen bench. Because I was still covered by the builder's warranty, I got someone from the building company back to check it out earlier this year. He removed the worst of the skirting boards to reveal a microcosm of fungal diversity flourishing under my kitchen. He told me to let it dry out and that he would return in a couple of weeks to have another look. He came back six months later. This time, he removed a much larger piece of skirting board that had become rotten so that he could inspect the plumbing. The amount of construction debris/rubbish that was still sitting in the cavity was absolutely astounding. The guy ended up pulling out 2 bags of decaying pieces of wood, nails, tape and even an old cigarette box...all of this rubbish had been left in situ when the builders installed the kitchen. Is it standard practise for builders to entomb rubbish in wall cavities and under kitchen cabinets? It makes me wonder what other treasures lie hidden away in my apartment.