Sometimes that may well be the case, there are a lot of thick people around. But when you have sites like DH Gate which are reliable being cheap as chips, some people will trust a wider range of sites thinking they’d be of the same ilk.
I remember there used to be a Ray Ban website that looked genuine but the glasses were about £50 instead of £150. I got up to the point of paying once but it would only accept credit cards and wouldn’t accept my debit card so I sacked it off as I thought it was dodgy, but loads of people would go through with it. I don’t think that site exists anymore.
My Father was stung by one of these kind of sites and they took a few hundred quid out of his bank for one t-shirt he ordered for about £12.
Plus a lot of the big scammers catch a lot of elderly or vulnerable people.
I watched some BBC daytime programme once, Crimewatch or something; the scammers found information on an elderly widower who once had a Timeshare abroad with his wife and the scammers got in touch saying that he owed thousands of pounds on it because of some changes after Brexit or something. They said the bailiffs would be coming round if he didn’t pay it so he paid thousands to them.
Although, as you say, there are a lot of thick people… on the same programme a woman had been scammed and she said ‘this is the fifth time I’ve been scammed now’, so you’d think the idiot would have learnt the first, maybe even the second time. But often it’s not just thickos who get stung.