crazybrit
If it there is bein Ie residue on bbq then Shouldnt eat during 9 days. IF the bbq is clean then the sausages can be eaten and dont make you fleishigs (though they cant be eaten w/ milk (unless bbq hasnt been used for meat in 24 hours in which case if cooked already (i.e. bidieved) can be eaten with milchigs, though according to most cant cook on bbq lechatchila planning to eat with milchigs)
sushibagel
“Doesn’t that defeat the purpose?”
Depends what you mean by “purpose” The purpose of the stores/restaraunts is to make money in which case advertising does the exact opposite of defeating the purpose! As for the consumer’s purpose once following his/her halacha/minhag and avoiding meat during the prescribed time. Any other purpose is between him and his rabbinical advisor