What should come into your business plan is how you assess it, how you foresee anything occurring that could have an adverse impact and how you would deal with it in the right ways. If you are looking to obtain funding from a bank or people you know, it is essential to show what the risk factors are in the proposed business and how you plan to defend against them.
I say that because of course you need to be careful with commercially sensitive ideas, as you do not want to pass your plan on to someone in the pub who then starts your idea before you across the road.
It seems to have been put there to fill the need to attribute a certain sum to marketing. Make sure you are researching each point of your budget, make sure that you are giving it context and it makes proper sense within your overall plan.
Whether it is travel, study, cooking or any other activity involving a process, planning is usually the first step. The same holds true for business. Business plans are probably more important than the business itself. For example, the plan for a house is more important than the house itself, though it is the house that people remember and not the plan. But the house wouldn't stand without the plan, would it?.
business proposal for ecommerce