I doubt about rivalry, his business doesn't make that much money, even after years of development and quite successful social media posts (I've heard about it a dozen times).

He needs to expand into other niches. Japan is full of weird things.

Thing is that even with the limited market he has some 5 serious competitors.

As bemmu readily admits competition is eating into his market.

You name the niche you will see competition no matter how obscure.

Small charges on stolen credit cards are usually to test if the card is still valid.

Hence charities are popular to test on too.

Ah, okay, makes sense (in an evil way).

It just sounded like it was a sudden wave after the site had become more popular, but it maybe just appeared on the radar of scammers as well as the competition.

I have long stopped telling people whether their charge worked if an order looks suspicious, to prevent them from getting this information. So that wouldn't work now.

I am not sure I follow, could you clarify? You do send a confirmation after sign up I presume?

Well I can't say "your payment was processed successfully", because that would give information to people who want to test cards. Rather I manually read through the orders, and only contact people if something went wrong with their payment AND the order doesn't look suspicious.

Are you on Stripe?

Can't find it but he had a whole blog post about it

So I guess credit card frauds are human too

Thanks, fixed the https issue.

Maybe I have a too rosy world view, but I don't think rivals would be this mean. Probably some simpler answer. Maybe there's some forum post somewhere like "how I got free candy by using this list of credit card numbers" and people keep trying that.

You're probably right; I've read of people's Google ranking being trashed by rivals using spamming tools, so maybe my world view is too dark. OTOH, I seem to be naive about how credit card scamming works.