Tom Cerber calls our attention to this article describing this study. Turns out that the repeal of Sunday closing laws has a negative impact, not only on church attendance and giving, but on certain forms of destructive youth behavior.
And while Im at it, one of the co-authors also has this paper, whose results are summarized here.
To be sure, these considerations should affect the behavior of public policy makers, not the attitudes of believers, who have other reasons for behaving as they ought.
Havent read the linked to articles, however, a lot of these blue laws have been upheld in court as legal despite their religious inceptions.