Today’s Muslim are divided into many sects. But if you deeply study all the sects you come to know about two major classification of Muslims. Surprisingly its not Shia or Sunni.
Almost all Shia’s praises Sufism beside a major chunk of Sunni’s as well. On contrary, Salafi’s negates the Sufi’s thoughts and opinion.
Salafi’s: are those Muslims who prefer the opinion of salaf-as-saliheen (Sahaba’s, Tabieen & Taba Tabieen) on different matters. The concept of shrine is unacceptable and consider Mushrik those pilgrimage who seek helps from shrine.
Sufi’s: are those Muslims who own’s spiritual thoughts and preferred the opinion of Great Sufi’s on others. Building shrines are acceptable and doesn’t consider it as a sinful activity.