A coluna bytea do Postgres está retornando string (array char) em vez de array byte

NpgsqlConnection conn = new NpgsqlConnection(connStr);
conn.Open();

NpgsqlCommand insertCmd =
    new NpgsqlCommand("INSERT INTO binaryData (data) VALUES(:dataParam)", conn);
NpgsqlParameter param = new NpgsqlParameter("dataParam", NpgsqlDbType.Bytea);

byte[] inputBytes = BitConverter.GetBytes((int)0);
Console.Write("Input:");
foreach (byte b in inputBytes)
    Console.Write(" {0}", b);
Console.WriteLine();

param.Value = inputBytes;
insertCmd.Parameters.Add(param);
insertCmd.ExecuteNonQuery();

NpgsqlCommand selectCmd = new NpgsqlCommand("SELECT data FROM binaryData", conn);
NpgsqlDataReader dr = selectCmd.ExecuteReader();
if(dr.Read())
{
    Console.Write("Output:");
    byte[] result = (byte[])dr[0];
    foreach(byte b in result)
        Console.Write(" {0}", b);
    Console.WriteLine();
}

conn.Close();

Input: 0 0 0 0
Output: 0 0 0 0

"\000\000\000\000"

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