I noticed that Sentry ico had no website, no Twitter and that everybody posting had Sentry logos in their post. It seemed like a scam to me so I commented and said I think this is possibly a scam and they instantly deleted my post like they had it automatically deleted based on the keyword scam. It sounds like a good project but realistically if a company is willing to spend millions of dollars to conduct an Ico they should at least have a website.
the sentry logos are because of the bounty campain, you can/could (not sure if it is still open) join the bounty campian then use their logo as Avatar. and their signature.
might be useful for spreading their word in other topics. At least I think that was the intended use of it.