https://fbcdn-photos-a-a.akamaihd.net/hphotos-ak-xap1/v/t1.0-0/10350354_10154868068150331_5314435252187030757_n.jpg?oh=9d4adfd849f7d3e69d4a21abb5cb88af&oe=54D51A81&__gda__=1427148244_49b8493632c56fb3cb754b6b808422f6 (Unsupported image host)



Its obvious isn't it? Admins checked your friends and his friends logs for inappropriate solicitation, ie, drug dealing.
they could be just joking around but if it was bad enough for a ban, your friend deserved it.