I think what people tend to forget is that many of the ocellaris that are available today are not wild caught. They were born in an aquarium environment and have never seen an anemone let alone what to do with it. I'm sure that they have instinct to go to it eventually but I wouldn't expect them to go right away.
My ocellaris took close to a year to host with my anemone and now will defend it from anything including my hand
Also, one theory that I have heard and believe to be true is that bubble tips create the bubble tips when they feel threatened. This is done to protect the vital organs from damage, like a human that goes into a fetal position. I know my RBTA's do this during cuttings, then the tentacles go back to non bubbled after a day or two.