What do you guys think of people buying gil?

[Shirai]

once someone buys gil from an rmt that rmt can hack your account so it makes more work for SE so it's bad for everyone

Uh, this has nothing to do with buying gil.
Rather this is a security issue, people falling for Phishing mechanics like the emails SE warns about, people using the same usernames and passwords on websites with inadequate security measures or RMT sites, not using a security token, etc. etc.

Buying gil does not magically make your character hackable.
And if you are stupid enough to hand out your login details to RMT you deserve it.