User-generated content (UGC) is quickly becoming the most popular marketing tool ahead of online influencer campaigns. The public have become accustomed to reality stars and has-been celebrities flogging whichever never-used-gadget that they’ve been paid to promote.

Since the rise of the Insta-marketeer, the Advertising Standards Authority has prescribed new rules for promoting products and services through social media platforms and online blogs, where a paid promotion must be...