Sometimes, it is ultimately less expensive to pay for the reception venue and use their catering service, than to find a place that does not provide this service and to have to find a caterer on your own. The more services you can consolidate, the better for your wallet. Many places will charge you to cut the cake and they charge by the slice. It is not inappropriate to ask a friend or family member to provide this service for you. They won't miss a single event of the wedding and will feel good about being included in your big day.
Alcohol is a touchy subject.
If you want to provide alcohol, consider offering beer or wine, but no liquor. Another option is to offer a special alcoholic beverage, such as champagne, among the standard beverage fare. If you want to avoid the subject altogether and save yourself serious money, have a morning wedding. No one expects a fully stocked open bar at a 10 a.m. reception. However, if you plan to have an evening wedding with an open bar, know that this will amount to one of the largest wedding expenses.