Remember the "I agree" button you click every time you download/patch League of Legends?
Remember the fact you literally cannot be accessing the client without downloading/patching League of Legends, and as such it is 100% certain you have clicked that button?
This is what you agreed to:
We may terminate or suspend your account if we determine, in our sole discretion, that:
(a) you have violated any part of this Agreement;
(b) we have stopped offering the Riot Services in your region; or
(c) doing so would be in the best interests of our community, the Riot Services, or the rights of a third party.
You have no ownership or other property interest in any of the Virtual Goods you unlock, regardless of whether you acquired access to those Virtual Goods using Riot Points, Influence Points or Hextech Crafting.
NOTWITHSTANDING ANYTHING TO THE CONTRARY HEREIN, YOU ACKNOWLEDGE AND AGREE THAT YOU SHALL HAVE NO OWNERSHIP OR OTHER PROPERTY INTEREST IN YOUR ACCOUNT, AND THAT ALL RIGHTS IN AND TO YOUR ACCOUNT ARE AND SHALL FOREVER BE OWNED BY AND INURE TO THE BENEFIT OF RIOT GAMES.
YOU HEREBY ACKNOWLEDGE AND AGREE THAT YOU HAVE READ AND UNDERSTAND THE FOREGOING AGREEMENT, AND THAT BY SELECTING THE “ACCEPT” BUTTON BELOW OR OTHERWISE USING OR ACCESSING THE RIOT SERVICES, YOU ARE AGREEING TO BE BOUND BY THE TERMS AND CONDITIONS SET FORTH HEREIN.
You don't own anything. It is Riot's account. You have "no ownership or other property interest" in your account (hint: it's not yours).
They can terminate/suspend your account if, in their discretion (read: for any reason they deem fit) it would be "in the best interests of... the Riot Services" (read: they can suspend your account if they want to).