You don't understand how secondary markets work.

Higher liquidity and lower spreads give an investor more confidence in their investment. They always have the option of getting out of the investment and at a lower cost. More confidence in an investment means the investor will pay a premium over the same investment that is less liquid and has higher transaction costs.

This premium means companies shares are valued more in the secondary market. This also means that companies can fetch a higher valuation and thus raise more capital in the primary market. Both of these are a win for investors and the companies themselves.