It's momoe0403's referral link, they should probably mention that - they get a benefit from you joining. It doesn't seem relevant to the post, for me this is just spam advertising so they'll get extras. You don't lose anything from joining from a referral (in fact, from a glance at it, you get a bit extra than if you joined without being a referral) however it's still shady to not mention it.

I think you have to actually purchase coins in the ICO to get the free coins.