No, they don't, not really, hence, tipping culture. But for catering, unlike menu price at a restaurant, you are paying full freight for service. You are also (compared to a restaurant) paying for the lack of upsell opportunities. (Particularly, if you are supplying drinks separately and don't have a cash bar operated by the caterer: the bar is disproportionately where restaurants make their money.)
I wish. Wedding vendors, especially catering, are also tip driven and its generally expected to tip individuals (coordinators, bar tenders, wait staff etc).
No, they don't, not really, hence, tipping culture. But for catering, unlike menu price at a restaurant, you are paying full freight for service. You are also (compared to a restaurant) paying for the lack of upsell opportunities. (Particularly, if you are supplying drinks separately and don't have a cash bar operated by the caterer: the bar is disproportionately where restaurants make their money.)