Android Room: Synchronous queries return null

I have a Site and corresponding SiteDao:

@Dao
interface SiteDao {
    @get:Query("SELECT * FROM site WHERE uid = 1 LIMIT 1")
    val site: LiveData<Site>

    @get:Query("SELECT * FROM site WHERE uid = 1 LIMIT 1")
    val getSiteSync: Site

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    fun insert(context: Site)
}

This works:

siteRepository.getSite().observe(activity, Observer<Site> {
     // `it` is instance of Site, working as intended
})

This doesn't:

Thread {
    val site = siteRepository.getSiteSync()
    // site is null
}.start()

Nevermind that I'm using Repository instead of ViewModel, just an example.

Any idea why?