Possible suggestions: it looks like it is 'just' retrieving one's list of subscribed subreddits then displaying manually curated lists for each category, which means every user who is subscribed to a subreddit will be shown the same products in this category.
I don't know if you are planning on continuing work on this project, but if you are adding more items implementing an actual recommender system could do wonders (for example, by looking at what users with similar subscriptions have favorited). I feel the Reddit-browsing demographic is one that would be very receptive to this type of thing since some subreddits are all about about social-based discovery.
I'm willing to guess one can learn a surprising lot about one's preferences by looking at their Reddit subscriptions. For example, you may be able to guess the clothing style of someone who is subscribed to r/malefashionadvice, r/newyork, and r/finance, or that someone who reads both r/audiophile and r/metal might like different headphones than someone who participates a lot in r/classicalmusic.