Why do some "e"tailers charge tax and some don't?

[PICK3]

even some "e" vendors in another state charge taxes now, but some don't

 

[superqt4u2nv]

even some "e" vendors in another state charge taxes now, but some don't

It depends on the State you are in for example if company ABC is located in Illanois and ship out side they do not technically have to charge sales tax for the state that is going to it is the customers issue to pay the sales tax on it. However say company XYZ has warehouses that they ship to across the country (Example on in Chicago and one in Vegas.) they must by federal law charge taxs in effect saving there customer from having to go back and pay the tax at the end of the year.