I agree that the switch to palm oil may be one factor, but is almost certainly only one of many.
Picture a lovely CF tale on MN, where somebody manages to convince you to host them for a month, expects you to provide all their food, plenty of booze, drive them around everywhere, let you have your bed and priority in the bathroom whenever they want a long soak etc. etc. - then, when they finally leave, they go through your fridge and empty it of all the 'leftovers' (that you've just bought fresh) for their journey home.
Well, these companies are the corporate equivalents of this: they find every little way where they can conceivably save themselves a few pennies at your expense. Every single stage where they can make things less pleasant for you because it costs them a little less, they will do in a heartbeat - and they (and their shareholders) would consider themselves absolutely crazy if they didn't screw you over in every possible way.
As a general rule, once a company is floated on the stock market and has thousands of shareholders, all quality and integrity disappears. The owners know this full-well: it's a conscious decision they make to take the money and sell their company's reputation down the river.
In contrast, when you get companies that retain ownership and overall control amongst the founding families/few originators, they tend to maintain their quality and integrity.