Why Google , Yahoo, Microsoft like only those Web Masters, whose Website and Blogs have huge number of visitors?
The straight-forward answer here lies in the blog title Why all Search Engines do not prefer to work with less Traffic generated Website and Blog? itself.
Webmasters whose blogs and websites have huge number of visitors will substantially carry huge traffic with them. With this huge blog traffic, very soon, that blog will come out of the Google sandbox and will receive serious traffic, and even loyal readerships.
This in turn will increase the search engines clicks and in turn the people searching for there stuff start holding a feeling of reliability towards the search engine.
For example a person googling a topic on how to bake cake can best trust the search engine if he/she gets satisfied with in the first page of the displayed results.
The same technicality lying here is the 'brand name' or say 'popularity' of the search engine.
The search engines do not rather want to carry bad names on themselves for displaying the blogs and websites which diverse the search results.
Due to the high marketing value of targeted search results, there is potential for an adversarial relationship between search engines and Webmasters.