Clearly then we're lucky you are not the one in charge at MAS.
Why put on all the extra weight for a meagre return in terms of benefits? Extra weight means loss of revenue and higher fuel burn. How does this help them out? For advertisement purposes, there are many other more effective methods and reaches a wider range of audience.
And it is a special scheme to promote the new premium cabins. They are called special for a reason, because they are only applied to select few (in this case, one) aircraft while the Hibiscus livery is applied on 2x B744s.
On the B744s for example, the new cabin alone increased the aircraft weight by quite a bit and the special paint scheme actually added a few tons, and hence a reduction in useful load. For long flights where full fuel is needed, less cargo can be carried.
Business is business. To make a business work, you have to think in a broad perspective and make smart decisions. Moreover, the airline industry at this time is particularly competitive.