Well mine is at 17 Satoshi too at the moment. I think the connection between halfed and regular reward is not a cut off, but a smooth connection, so the more you spent, the more your bonus will go up until it finally reaches the regular reward.
The reason for your friend getting a differnent reward than you is that there are many factors to take into account. Besides the lottery tickets bought also the amount wagered in Multiply and the balace of your account is taken into account. Although there are only few information on this, it was confirmed that if you hold 50$ worth BTC in your account, you will get the regular reward. I would assume that your friend has either wagered more or a higher balance than you. Furthermore I assume the amount you already won in Free Rolls is also taken into account, so not the absolute amount spent in Lottery and Multiply is relevant but the relative amount of everything you claimed so far. This would mean if your friend has won less in Free Play it could explain the difference too.