clapping during hymns?

i went to a baptism last night (fashionably late as usual, for a church function) and as i arrived i was surprised to hear that the closing hymn was 'this lil light of mine' and SHOCKED when i heard a few people in the audience CLAPPING ALONG, southern baptist style.

i had heard that they added some hymns recently and granted it's been some time since i've been to anything like this but clapping in sacred settings was SUCH a big no in the church that i grew up in. is this how it goes down now? are they clapping in sacrament meeting?

should note that this was outdoors at a private residence rather than a church building but it was still surprising to hear during one of the more sacred ordinances.