Originally Posted by AnemicOak
Just time is all I can think of. You'd think it should be worth the extra effort, Kobo too, but at least for some of the authors I've talked to who have tried both going through all stores and doing KDP exclusively with the Kindle Owners Lending Library and they've found, in the past at least, that library payments from Amazon made them more $$$ than having the book non-exclusive and at the other stores. Something I'm sure is highly author and genre dependent.
That makes sense if going exclusive or all stores are the only options. And maybe that is the only two options, realistically.