BCBrian... given that your intent in asking this question appears to be honest and genuine, I'll give you a straight answer.
It is considered a matter of honor to attend a slain brother officer's funeral. While the actual mortuary expenses are covered by the department in question, the rest of the spectacle you see on TV and in the papers is not paid for by tax dollars. Nearly all the people in uniform at a police funeral are there on their own dime. Some agencies will send a formal representative or two, and these officers (usually command staff) MAY draw pay for that day, but it's part of their administrative/command responsibilities in any case. The rank and file coppers who attend are off-duty but in uniform, and if within driving distance, they'll be issued a squad out of the motor pool for the procession. The cost to the department is minimal... a tank of gas or so.
Most of the cops attending won't even submit their meal expenses for reimbursement. The pipers and buglers are likewise there on an honor basis. (I know of several who travel all over the country at their own expense to offer their musical services.) The floral arrangements are commonly paid for by the local patrolman benevolent association, which means the money came from cops and from fund-raising activities.
The solemn ceremony of a police funeral is a reflection of the honor of the police community, and a reflection of the sincere emotion felt over the loss to that community the officer's death represents. How much is too much? It can never be too much.
