Why is there bamboo in my alpaca?

I have a batt of perfectly lovely black alpaca that I'm trying to spin thin for lace.  I was struggling with not only how extremely slippery it is but also how there are weird snarls in it where it looked like long fibers got bent back on themselves.  I thought that was awfully strange since it's a carded batt of alpaca.  After digging out the label I found it is 80% alpaca and 20% bamboo.  Now why on earth would someone put bamboo in my alpaca?  It doesn't add elasticity or length or even any shine (not enough to even notice).

On to the good stuff.

I got so excited when I found this that I had to go out and get a support spindle.  I even ordered a matching set with a bowl that are being made this weekend.  I self taught myself to spin on the support spindle after watching these videos of Fleegle spinning.  More information can be found at Fleegle's blog for anyone interested.  I am now impatiently awaiting the arrival of the new book because I have soooo many questions.

I was able to spin my singles like this on my new spindle.

Unfortunately I still can't get them very thin.  I keep spinning this size which is my default spinning thickness.

This is what it looks like plied.

Maybe if I keep going I'll get the hang of it.