Alright, so it's currently like this:
The source code was a little bit buggy to begin with. You were NOT supposed to be able to use two Blazer clips at the same time, but due to a small coding mistake, it worked, but as I said, looking at the source code, it was NOT intentional. So it's now like it's supposed to be: if you equip two items that give additional item drops (the SAME item drops), only the higher rate will be applied, i.e. if one item grants a 10% chance to drop a food item, and another item grants a 20% chance to drop a food item, only the 20% will work. It does not stack, and they do not work separately (as it was previously).
However, if you equip two items, and both of them add a DIFFERENT additional drop, like one item gives 10% food and the other one gives 20% gift boxes, both items WILL work.
As you could call it an official bug fix, I'm kinda opposed to change it back to the way it was before... I mean the people who use it as a way to make money could always use one blazer and one mimic or any other accessory card that grants additional item drops, although the profit will be a bit less, since food items are, for some reason, ridiculously expensive compared to other items... will have to discuss this with the whole staff, though.