When a girl runs er account herself, it's not that unlikely that you'll receive "gifts" (free AND paid) on your DMs if you tip enough or become part of the top spenders on a given month, especially if it's more than once. I've been there with girls with smaller fanbases. As kids say, I don't have proof, but I also don't have any doubts that she does this.
Girls can see who tips what. From there, it's easy to have DMs with them separated from the rest. And since this is sensitive content, of course she'll be more careful.