On the one hand, WW is designed to allow us to have those splurges like that. But, on the other hand, I've done that before and felt awful. I went on a "diet break" back in April and didn't count anything and just felt so sick by the end of the few days.
I think it's one thing if we purposely budget to eat those onion rings and it's another if we didn't plan on it and end up eating them anyway, possibly going over points or whatever.
As for homemade, I've never tried them, but I've been using a new cookbook lately called
Appetite for Reduction (it's a great cookbook even if you aren't vegan (I'm vegetarian)) and there is an onion ring recipe in there I've been meaning to try. A friend of mine did it and said it was really good.