Apart from the drunken idiots, the main reason this seems to keep happening is the 1:00 a.m. last call. If bars could stay open to 3 a.m. you would not have the big rush right at closing time. Lots of people will stay out to 1:00, but beyond that many people will gradually head home. Certainly you will have to kick some people out at 3:00, but I'd bet it would be less than half as many people.
"Police estimated about 300 people were on Wharf Street. As police were arresting Moultrie, who is 6-foot-3 and 235 pounds, a crowd gathered and began yelling at the officers, accusing them of racism and brutality, said Lt. Tony Ward, head of detectives for the Portland police.
Additional officers were summoned to keep the crowd back and some bouncers from area bars stepped forward to help the police." - Portland Press Herald