Well, I am divorced now so can't be a SAHP anymore, but what I did love;
Being on my own clock
Answering to myself (vs some jumped up twat who has been appointed Queen of the Office Realm)
Being able to cook at a leisurely pace
Being there for the kids when they're sick
Being there for the kids when they've had a bit of a crap day
Being able to shop during the day instead of rushing about, exhausted, on my way home
Being more in touch w the seasons from walking to shops, walking w kids to library, park, & school (versus being stuck indoors from 9-5)
Not being bored to death by boring busywork all day long - I found being a SAHM (when the kids were little and early school years) about 1000 times more interesting than work.
Probably more things! I hate working, I love taking care of my family, cooking, cleaning, baking, gardening. I'm a domestic person and it kills my spirit going to work.