Did those brands design their own epoxy formulations and build an epoxy manufacturing facility? Or did they go to an existing epoxy manufacturer and ask them to package up some epoxy and put their brand on it? I don't know.
The acquisition or the rebranding of another company's product is pretty common. There are many items with just a few direct manufacturers and factories willing to slap a name on something. Or willing to work with an established name to make a product that would differentiate themselves in actual use. That's the hard part for consumers to figure out- is this a standard product with a high-end name slapped on, or is it a 'better' version of the normal product justifying the extra cost?
If this was a digital camera forum we could try to figure out what makes some Leica digitals worth so much more than the Panasonic digitals.