I've been wondering what the DDF LOR says about multiple Venmo accts.
I personally think its assur to open more than one, since every cc charge cost them money, and they are suffering the loss in order to gain another user. Hence saying you are a second person, when you really are the same is outright stealing, IMHO. Even assuming none of the owners/investors are Jewish, we pasken Gezel Aku"m is assur (as a separate issur, not onlyy when C"H is applicable).
I don't however think its a problem opening an account for young kids, as they are another 'person' and are given by Venmo a right to an acct, even if its reall me that's using it.