Azzi, the camp I attended in the mid-sixties had been doing "closing songs" (quiet, meditative, get the kids ready too sleep) with arms crossed and holding hands for much of the history of the camp. It was founded in 1918. By the mid sixties the camp was integrated and well versed in protest songs. It is where at 12 in 1968 I learnt We Shall Over Come, and United Nations and Crayon Box those songs were not sung arms crossed. Green Trees/Peace and Taps were a more likely combination.

There are ties between the Civil Rights and Camp communities.

Camp Wo-Chi-Ca (Workers Children's Camp) was started in 1933, as the first interracial camp in America. It existed until 1951. Paul Robeson was on its board of trustees and was a frequent visitor and honored guest. The site now holds a joint Episcopal/Lutheran Camp and Retreat Center. You can see his camp theatre space half way down this page Paul Robeson Recreational Hall
My own guess is that there are countless ties between the two traditions that would be difficult to separate.