"Mwahahaha!" the human kicked open the door to Carousel Boutique, twirling his mustache menacingly. "I have defeated your door, and now you will fall before my wiley human wiles!"
"Oh no, this is horrible!" Rarity gasped, covering her mouth with her hoof in sheer horror at the monstrosity entering her shop. Because it simply wouldn't do to allow anypony see her jaw drop in horror. Most unladylike.
"Mwahahaha!" the human chortled at his good fortune, having finally found a helpless pony. "I am immune to magic, and so...wait, what are you-hurk!"
Never one to allow such a horror of a fashion emergency to go unanswered, Rarity grabbed the human by his conveniently not-magic-immune clothing and telekinetically lifted him up onto the measuring station. This would be a difficult client, but Rarity was a professional, and one way or another, no guest of hers was going to leave the boutique without looking magnifique.
Yet another rule of antimagic, the mere fact that you are immune to magic, doesn't mean that your accoutrements are. On a related note, you should ensure that your various armaments enjoy the same protection as your own self, lest a safety be reapplied mid-gunfight, or a grenade surreptitiously lose its pin.
wait
wasn't it a anti-magic bubble?
The magic shouldn't penetrate into the bubble in the first place... That was... Eugh.
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The problem is an earlier chapter was based around the fact magic can't penetrate the barrier and instead was turned into raw energy.
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You, uh, did actually read that chapter, right?
The whole point of this story(as we understand it) is that every chapter has its own rules that are subdued via various means.