They do like upselling and I find that annoying. (I've just been to an optometrist for new glasses and had some difficulty actually getting the $59 basic glasses rather than the "second pair free" super thin, all bells and whistles for $700+. Most annoying! I just wanted cheap reading glasses to see if I would actually use reading glasses.)
I find the Seanik conditioning enough for me and haven't bothered to purchase any conditioner.
The "un-oiliness" as you call it is a remarkable effect. I eventually decided that it was more that there's no residue in my hair to attract and hold dirt.
And yes, a little tiny round bar in a matching round tin is exciting, compared to two huge bottles of shampoo and conditioner. My first bar has lasted me 6 months so far and has travelled around the world with me for 3 months.