Superstore:Coffee confusion

Upon checking to determine if President's Choice Gourmet whole bean coffee, we at KV noticed the pre-packaged PC Gourmet Coffee carries an MK hechsher. However, there was no pre-packaged PC Gourmet whole bean decaffeinated coffee, so we scurried to the computer to look up PC Gourmet Coffee on the MK website.

No luck.

However a search brought up the COR site. According to the COR site, all President's Choice Gourmet whole bean Coffees are COR certified, including the decaf.

So then why do they carry an MK hechsher?