Well, the McKinley presidency (1897-1901) brought an economic boom along with a surge of confidence to American society. People were prospering and institutions were thinking grand thoughts. This continued on into the administration of Theodore Roosevelt (1901-1909). So, congregations and denominations were thinking big, and even modestly-sized congregations could afford to build in stone. This was especially true here in southern Indiana, where the limestone quarries were booming, too, and the stone was locally sourced.
I don't know too many churches which could afford to build in stone today. Pole-barn technique seems to be the most popular for new church construction, along with stick-built. Any stone or brick in evidence is veneer only.