I love to shop at the thrift stores that benefit charities, do you?
They are ok. The best things to get at thrift stores is clothing.  But it is still a business that feeds a capitalistic venture. 
Oh in my area its a retail establishment run by a charitable organization to raise money
Yes they raise money and meet a minilnal requirement to legally be considered charity but they still have a CEO who owns a mansion. . 
Oh ok are the people that work there volunteers?
I don't know.  Maybe some are but they also have dedicated employees and operating costs to remain in business. 
Is it easy for them to make a profit since most items are donated to them?
Charity shop
A charity shop, thrift shop or opportunity shop (colloquially referred to as an op shop) is a retail establishment run by a charitable organization to raise money. Charity shops are a type of social enterprise. They sell mainly used goods such as clothing, books, music albums, DVDs, and furniture donated by members of the public, and are often staffed by volunteers. Because the items for sale were obtained for free, and business costs are low, the items can be sold at competitive prices.
Web Thrift Store
Web Thrift Store is an organization based in New York City that facilitates non-profit organizations to raise money through it. It was founded in 2011 by Doug Kurgman and Lynn Zises.
History.
Web Thrift Store was founded in 2011 by Doug Krugman and Lynn Zises in New York City. The stated goal of the company is to allow non-profit organizations to run online thrift stores without having to maintain inventory. Part of the reason the two founded the organization was to get people to donate