A regular KakaoTalk channel has most of the features that would be needed for small business including a customizable user ID that’s searchable in-app, posts for user newsfeeds, messaging, channel performance analytics, and promotion coupons.
Business KakaoTalk Channel is intended for larger enterprises, and includes additional features such as:
Business channel badge - increases the credibility of the channel because KaKaoTalk user will have increased trust with an official channel
Biz Message (AlimTalk, FriendTalk, ConsultationTalk) - enable business to reach out and engage with KakaoTalk users
Priority given to a business channel to be displayed first when the user is searching on KakaoTalk
Additional exposure for example, using a "recommended channel" in KakaoTalk.
Comparison of Standard KakaoTalk and KakaoTalk Business