Okay, although to be fair no evidence besides history was provided by the other side

The primary motivation for creating the Federal Reserve System was to address banking panics. Other purposes are stated in the Federal Reserve Act, such as "to furnish an elastic currency, to afford means of rediscounting commercial paper, to establish a more effective supervision of banking in the United States, and for other purposes." Before the founding of the Federal Reserve, the United States underwent several financial crises. A particularly severe crisis in 1907 led Congress to enact the Federal Reserve Act in 1913. Today the Fed has broader responsibilities than only ensuring the stability of the financial system

The Federal Reserve serves to ensure that banks don't go overboard with their money.

Bank runs occur because banking institutions in the United States are only required to hold a fraction of their depositors' money in reserve. This practice is called fractional-reserve banking. As a result, most banks invest the majority of their depositors' money. On rare occasion, too many of the bank's customers will withdraw their savings and the bank will need help from another institution to continue operating. Bank runs can lead to a multitude of social and economic problems. The Federal Reserve was designed as an attempt to prevent or minimize the occurrence of bank runs, and possibly act as a lender of last resort if a bank run does occur.

Ah, that sounds pretty beneficial to creating a stable market and to prevent the abuse of bank customers... or at least minimize it.

The Federal Reserve has the authority to act as “lender of last resort” by extending credit to depository institutions or to other entities in unusual circumstances involving a national or regional emergency, where failure to obtain credit would have a severe adverse impact on the economy

This ensures that our banks won't run out money which would cause severe problems for the economy.

Through its discount and credit operations, Reserve Banks provide liquidity to banks to meet short-term needs stemming from seasonal fluctuations in deposits or unexpected withdrawals. Longer term liquidity may also be provided in exceptional circumstances. The rate the Fed charges banks for these loans is the discount rate (officially the primary credit rate). By making these loans, the Fed serves as a buffer against unexpected day-to-day fluctuations in reserve demand and supply. This contributes to the effective functioning of the banking system, alleviates pressure in the reserves market and reduces the extent of unexpected movements in the interest rates. For example, on September 16, 2008, the Federal Reserve Board authorized an $85 billion loan to stave off the bankruptcy of international insurance giant American International Group (AIG).

This lending policy prevents supply and demand variations from taking out lending institutions.

Federal funds are the reserve balances (also called federal reserve accounts) that private banks keep at their local Federal Reserve Bank. These balances are the namesake reserves of the Federal Reserve System. The purpose of keeping funds at a Federal Reserve Bank is to have a mechanism for private banks to lend funds to one another. This market for funds plays an important role in the Federal Reserve System as it is what inspired the name of the system and it is what is used as the basis for monetary policy. Monetary policy works by influencing how much money the private banks charge each other for the lending of these funds

This part of the federal reserve is vital because it allows banks to lend to other banks and gives them an organized way to do it. This also gives the ability to the Federal Reserve to move around interest points when they need to be moved around --aka monetary policy.