If an account is tag with a red trust often means that account should not be trusted or apply caution when dealing with the account but sometimes not all accounts with a red trust are untrusted because such accounts have equally done so many good things to over shadow the red tag, some red tag account did not actually scam anyone or something of that nature but maybe for other reasons,
My point is, just because an account has a red tag don't necessarily mean that account is bad, especially the example you gave above,  wapinta has handle so many good bounty as well as some bad ones,  there is nothing wrong in participating in his bounty.