How important role play breadcrumb in any website ??
since you posted this questiuon in the Search Engine Optimization forum, the answer is: none
Agreed, it’s a fantastic method of assisting users with the information architecture and usability of your website (if you implement one properly). 
It allows the sites visitors to see where abouts in the site they are. It’s especially useful where content goe several levels deep.
A form of text-based Web Site Navigation that displays a series of sequential links so that users can see where the current Web page is located within the Web site.