They absolutely are getting paid. This is from a relatively small blog post from 2 years ago addressing how she makes her money.
Brand Deals, Sponsorships, Collaborations & Campaigns
...Depending on your social media influence, your followers and content, you can earn between £350 – £50,000 (sometimes less, sometimes more) on a brand deal/sponsorship. A sponsored post/video is usually just that, where as a collab or campaign may be over a longer period of time, involving various social media activity. For example; being paid to attend LFW on behalf of a brand. I hope I’m making sense here.
Paid For Social Media Activity/Interaction
This would usually fall into the category above because usually in your contract for any paid work, it will ask for your support for the content on your other social media sites, however sometimes you will solely be paid to Tweet or Instagram something. I recently got involved with a body confidence talk on Twitter & that was paid for. Sometimes a company or brand would like some promo so they will pay you to mention their product. Its all in the name of advertising really.
Almost all the bloggers I have read in the last 10 years I've been reading them are now doing this full time and many of them live alone. Most of them are with a network who will take a cut of the cash, which has "books" in the same way a model agency does.