Gratuities for all three -- bar tenders, coat check and valet attendants -- should be listed in the venue and/or catering contracts and paid through those bills. Make it clear to the catering/location manager that you do not want tip jars/bowls/plates displayed since you are covering gratuities.
If you do see them out while your wedding is happening ask, or have someone like a bridesmaid or groomsmen ask, the manager to have it removed immediately.
