许多 ERC20 代币都包含UniSwapRouterV2在他们的合约中。这样做有什么好处？不包括路由器可以吗？

例如 的路由器代码：

// pragma solidity >=0.6.2;

interface IUniswapV2Router02 is IUniswapV2Router01 {
function removeLiquidityETHSupportingFeeOnTransferTokens(
    address token,
    uint liquidity,
    uint amountTokenMin,
    uint amountETHMin,
    address to,
    uint deadline
) external returns (uint amountETH);
function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
    address token,
    uint liquidity,
    uint amountTokenMin,
    uint amountETHMin,
    address to,
    uint deadline,
    bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountETH);

function swapExactTokensForTokensSupportingFeeOnTransferTokens(
    uint amountIn,
    uint amountOutMin,
    address[] calldata path,
    address to,
    uint deadline
) external;
function swapExactETHForTokensSupportingFeeOnTransferTokens(
    uint amountOutMin,
    address[] calldata path,
    address to,
    uint deadline
) external payable;
function swapExactTokensForETHSupportingFeeOnTransferTokens(
    uint amountIn,
    uint amountOutMin,
    address[] calldata path,
    address to,
    uint deadline
) external;
}