Great, but why? What it is about B that justifies the different ethical/legal criteria? Surely it's not the fact that eridius applied the label "experiment" to one and not the other?
How can it make sense to say that doing X is ethical "as long as you're just trying to make money, not publish scientific results"? Presumably, certain things are just wrong to do for whatever reason, and that is why scientific bodies user their publishing standards to prevent them from happening. Those reasons are surely just as applicable in other contexts; if scientific bodies don't have rules for those cases, its because they have no influence there, not because they think it's hunky-dory outside the lab!
"Well, yeah, MegaCorp burned people alive, but it's okay because they were just trying to make money, not publish results on human flammability."
How many more different ways can commenters make the above point, so that people will stop replying that "what advertisers do is not a Real Experiment, so they deserve a lesser standard"? That's a restatement of the inconsistency, not a resolution of it.
This is very different from the colloquial use of 'experiment' to talk about an A/B test or similar. It's a very specific context where we have very specific rules in order to prevent people from committing horrendous acts in the name of obtaining greater understanding.