Krysten Wagner, a Los Angeles–based TikTok influencer, is defending her decision to promote products on TikTok while wearing a face mask that’s on sale for $50. In a video from June, Wagner squeezes white cream from a shiny blue tube and begins applying it to her taut, perfectly clear skin. “If you’re not familiar,” she says, smearing the cream on her forehead, “you can now shop in the TikTok app.” For the past few months, she has been experimenting with a new TikTok feature that allows users to buy the products that she mentions in her videos directly through the app by tapping a little label with an orange shopping-cart icon. Not all of her followers have taken to it kindly. In the comments, some complain that these videos hawking products are flooding their feeds with what feels like sponsored content. She assures them that she has no relationship with the brand. She just genuinely likes Summer Fridays’ Jet Lag Mask! If “you really hate” her and don’t want her to get a commission, you …