Splinterlands ban players from using Splinterlands site and nothing more, you can move your assets/tokes using others hive dapps. In the same way, when they ban an account is because they violated the TOS in some way, mostly is due selling/renting cards between owned accounts to ëxchange"credits to DEC or doing paypal chargebacks, for example. However, everyone can appeal a ban and they will check it out