I do get emails from Kobo once in a while about books discounts, is that what you mean? I was unable to find books of my interest in the discounted section unfortunately. Amazon has also discounts once in a while and sometimes they offer a first book of the series for free, if you get hooked and want to keep reading you'll buy the rest still saving a few buks on a freebie.
Same title is cheaper on Amazon than Kobo, not by much but why to pay more? If it's not possible to buy a book YOU want with a discount, why bother with other discounted books if you're not interested. Or am I completely wrong here??? Sorry been buying from Amazon for ages, just recently got a Kobo Mini but keep buying from Amazon as I'm also got used to using their store.