Shot trap once at a place that had rules that said "unloaded till your turn." Something like that. To me it meant, "don't accidently discharge firearm and 1 shot per clay." If the other shooters are expecting 1 shot only, they might be surprised/grumpy when the guy before them shoots twice.
Looking forward to "trapping" again this spring with my short barrel installed on my 870. I'll have to hit them when they are closer to get a good hit (clay disappears in cloud of dust
).