You didn't mention the real reason: they are insiders. All the rest are details, nobody can ''move first'' and randomly buy a shitcoin without knowing its potential, or just guessing ''ah, it's a good idea, a nice narrative, it will probably pump''

Agencies mostly offer about a 10% fee and it's high for you, but I see some Chinese agencies give very low fees like 1-3% only, it depends on your spending I think, you can try looking for them on the Hire a Freelancer forum Anyway, from my experience, there is no long-term Facebook ad account...