What are the main differences between stake holders of project and vendors ?

Stakeholder means that their profit/business related and affected by the decision made by the board of company, now vendors are the suppliers, which depends on different of view if you know Porter Five forces, for example is it sole supplier, or are there are suppliers, so it vary depend on the strong position, if it is weak, it can be substitute with another supplier.

Stake holder of project are the investors, the financial hand of the company for flourishing, they already invest, so their profit comes from flourish of the income. 

vendors are  positive stake holders they are interested and affected by ongoing project operations and activities.

A project is successful when it achieves its objectives and meets or exceeds the expectations of the stake­holders. But who are the stakeholders? Stakeholders are individuals who either care about or have a vested interest in your project. They are the people who are actively involved with the work of the project or have something to either gain or lose as a result of the project.

A vendor, also known as a supplier, is an individual or company that sells goods or services to someone else in the economic production chain. 

Vendors are a part of the supply chain: the network of all the individuals, organizations, resources, activities and technology involved in the creation and sale of a product, from the delivery of source materials from the supplier to the manufacturer, through to its eventual delivery to the end user.

Having suppliers and vendors on a project team can be a very rewarding experience, and is very often a necessary factor of success. As a project manager, the way you engender the philosophy of your team to work with suppliers and vendors sets the stage for the success of all parties involved.