The symbolic act took place this weekend along a stretch of County Road 98 in rural Polk County that was anointed with oil by a Christian group last year.
"To symbolically welcome everyone, all citizens, whether they believe or don't believe," Rob Curry of Atheists of Florida told WFTS-TV in Tampa. "We're not doing anything to harm anyone. No gods will be harmed in the washing of the roads."
The ceremony took place in an area where Christians spread oil and prayed for a revival during the Polk Under Prayer campaign.
One of the organizers of Polk Under Prayer said the church folks weren't out to offend anyone either. "Mainly we want this to be a safe haven for folks who want to raise their families," Richard Geringswald said. "Asking God's protection from ne'er-do-wells and evildoers."
But some atheists say they are concerned the ne'er-do-wells and evildoers include people who don't share the same faith as the Polk Under Prayer members.
"This anointment ritual was to call out the angels to check each car that entered the county, to make sure they were Christian, and if they weren't Christian, they would either follow Christian beliefs or get put in jail," Ellen Wachs, president of Humanists of Florida Association and Atheists of Florida, told ABC News.