Where the heck are you people from that an open bar cost 10 grand plus the meal? My whole reception cost $5300($53pp 4 course meal, cocktails,5hr open top shelf bar and italian cookies. Cake was separate) Now granted that was 10 years ago but I check prices today and they're running about $75 & up same package. This was Southern CT(The Gold Coast as it's called) in a popular,prominent facility.
It absolutely can cost that much. Our bar bill for 225 guests was about the cost of your entire reception and, as I mentioned in a previous post, we have soda offered all night, beer and wine for 2 hrs, wine with dinner and one hour full open bar after dinner. So yes, depending on the venue and number of guests, I can see how it could approach the 10k range.