Do not be scammed by the phrase for free, as no one gives anything for free. It is also better to remove kYC part, give the prize in specific token and it does not necessarily be in US dollar.
"There is no free money on the internet" For this point I disagree, Uni, safepal and the popular now TKO are some example project that gives free money and I earn so much from this
All the examples you mentioned do not promise users to get free money. They were promised money that they would get in a certain token and the price of that token might drop to zero.