I don't think you can know 100% for sure, but if an advisor is heavily slanted towards all green *thumbs up* and no red or yellows, then it raises an eyebrow for me personally.
I've heard that Bitwine considers it a violation for readers to do that now...thank God. But up until very recently advisors got away with a LOT of copy and paste.
What these advisors would do is refund the clients 50 cents out of the $10 deals if s/he feared a bad review, then block. This would prevent a bad review because a $10 payment is required for a customer to leave feedback.