I have never been a fan of payment by installment. Infact I see it as a red flag and the need to take to my heels. Like you rightly said, it is just a beautiful way to rip you off while making you believe they are doing you a favour of having what you want or need and paying at your convenience. You always end up paying more than the man who saved up to pay once.
I love Jumia but I am never a fan of their black Friday because I know it's an illusion so i wait for the craze to be over and then buy on a good day. Their prices aren't so bad cos I have had to compare some of their goods with market prices and considering transportation and other factors, I think it is not such a bad deal.
I think Jumia sells things way cheaper than konga although there are products you'll see on konga, Jumia wouldn't really have them. I've actually used these outlets to shop quite well in the past and I know how they make money taking advantage of people. But we can agree that they provide comfort even if we might not exactly get the quality we want.
Oh yes they provide comfort and also privacy if you know what I mean 😉. I have not shopped on konga and you are right cos I've heard same complaint before.