To date, nothing would happen, because the new EULA applies to Minecraft Version 1.9.3 and above.

If Cyp updated the Server without changing the perks and someone would report, he would eventually get a warning message from Mojang at some Point. If he doesn't comply, his Server would probably get blacklistet, so the Server won't be reachable through the Standard Client.

 

Actually very true :/

 

Well technically no items from /buy give an unfair advantage considering $10 usd = 100 Dias and /kit wool isn't worth 100 Dias nor does it give you an advantage.