Service tax rate on event management services

i know the normal ST rate is 15%..................thanks for that but my question is not that 

I FOUND THE RATE ON THE WEBSITE OF CBEC, I WANT KNOW THE REASON BEHIND IT.

A)    Date of Introduction:

16.08.2002 vide Notification No.8/2002-ST, dated 01.08.2002.

(B) Definition and scope of service:

(i) "Event Management" means any service provided in relation to planning, promotion, organizing or presentation of any arts, entertainment, business, sports, [marriage]* or any other event and includes any consultation provided in this regard;

(Section 65(40) of the Finance Act, 1994)

(ii) "Event Manager" means any person who is engaged in providing any service in relation to event management in any manner;

(Section 65(41) of the Finance Act, 1994)

"Taxable Service" means any service provided or to be provided, [to any person], by an event manager in relation to event management.

(Section 65 (105) (zu) of the Finance Act, 1994)

(C) Rate of Tax & Accounting Code:

(Rate of tax is effective from 24.02.2009.)

 Courtesy: https://www.cbec.gov.in/htdocs-servicetax/st-profiles/event-mgmt