I just don't find them interesting. The aliens explaining things joke gets old real quick, and the rest of the humour is the same as in every other comic.
I mean, it's better than garfield, but that's not a high bar.
I think it's 10% funny, 85% cute and 5% clever.
I am entertained, I smile at them, makes me see the world in a slightly different way. Overall they are worth the 30 seconds I take to look at them.