Grey zone there for me.
I always see 2 parts:
1:
Animal does not get hurt, gets something he likes. Is happy with it. All is fine to me with that.
2:
Human ethics: "I am doing it just for personal gratification. I am so evil" sort of thing.
1 is the red line. 2 is the grey zone depending on how good your ethics are.
Basically it is that cow that got off by getting her teats squeezed and felt it was wrong to let the farmer milk her ?
Edit:
I forgot the practical bit:
If you smoother yourself in something that drives your dog crazy... expect hom to be on a frenzy and possibly happily bite your sensible bits.
Hence it is erroneously called "baiting" when it was ment yo be "biting" ?
So, if you can't afford a dog dish, it is totally Ok to feed him on your hand or whatever ?