I'd take any freebie over a Stella, etc.
I agree it stands to reason a daylily order should include another daylily. It's nursery, could be a newbie filling orders, could be an overabundance of Asiatic return. If I were a vendor and had an abundance of a particular flower that might not sell? Great gift plant...
Simple business. Gifting plants gets them "out there", better than watching them rot. Pic posted looks pretty nice, I'd try it.
If it were a hybridizer that only sold daylilies I'd question the gift plant more but I'd still stick it in a pot or in the ground. You might love it.
I know you're going to plant it and watch. Best of luck!