With all due respect to your work, somehow I never understood the "t-shirt" startup idea. We live in a world where there are many problems to tackle in health, science, government and politics, yet I've seen dozens of attempts at these t-shirt startups.
I do not mean to discredit your work, that being said.
Probably because the OP was able to create this in a weekend or less in hopes of generating some passive income. That really doesn't compare to any problem (trivial or otherwise) in the areas you mentioned.
Its a $17 billion dollar market that has many ways of being served better. The OP did say that it was just a weekend project and we all have to start somewhere. Elon Musk's first company was an internet city guide.
You can pretty much use this rationale with 95% of the internet businesses out there. Why try to produce a film via kickstarter when you can go to Africa and volunteer... etc.
I do not mean to discredit your work, that being said.