Over at First Things, there is a discussion about why Baptists who tend away from Arminianism would often be called “Calvinist Baptists” but never “Lutheran Baptists”. Read HERE and HERE. Both authors make good points, but the real reason is very simple:
Calvin and Arminius both agreed that Baptism doesn’t do too much, and the Lord’s Supper isn’t. (I mean, The Lord started it, but he only attended the first one. Nowadays it would better be titled “Our Remembrance Meal of the Lord who Isn’t Here At All Because He’s Glued to His Throne In Heaven.” Although that is a little bit unwieldy.)
While there may be certain affinities between Luther and Calvin regarding the will of God as it relates to salvation, Luther, like Rome, follows the teaching of the ancient church, the apostles, and the Lord Himself in saying that Sacraments actually do something. That’s also why, despite certain affinities between Rome and Arminius regarding the role of the free will as it relates to salvation, Arminians are not called “Catholic Baptists”. (That and a seething and lingering hatred toward Rome on the part of the Zwinglio-Arminians.)
The Reformed may vacillate between Arminius and Calvin, but they have no interest in the deeply and unswervingly sacramental theology of Luther. This is why no Baptist would ever accept the label “Lutheran Baptist”. Because while you might be able to uphold most of Calvin’s Institutes and deny the Sacrament to the wee ones, you can’t do anything of the sort while seriously claiming Luther as a theological father. It just doesn’t work.