The distinction between a hobby, no matter how passionately engaged in, and a business, is critical, and not only if you plan to appear on Shark Tank. It is critical when appearing before the IRS, too. Business expenses are deductible. The money spent on a hobby is not. This has particular implications for company owners. Incorporating, alone, does not mean the IRS will call it a business.
Let us consider the owners of wildly successful car dealerships who also own stables through a separate company. The stables conducted some business – giving riding lessons and boarding horses, but mostly for people the owners knew. They did not advertise. Predictably, the company owning the stables was losing money arm over fist. The taxpayers owning both ventures wanted to deduct the stables’ losses against the dealerships’ profits, lowering their tax liability. The IRS said no. (Full disclosure: to make the point easier, this is inspired by, but does not exactly reflect, an actual tax case.)
Putting different ventures under different companies is wise. Thinking that something will automatically be deemed a business by the taxman because it is owned by a company is not. Having a good accountant and a good tax litigator on your side is wisest.