I feel like buying some stock in Tesla to make a contribution toward our future, not in the hopes of making money.
If these shares make money, that will be a bonus.
If these shares make money, that will be a bonus.
However, supporting the existing stock price could have an effect - typically the market price influences the price of a secondary offering like this.
As you say, the market price has an influence on secondary offering prices, so it affects a company's ability to raise further funds, but buying stock secondhand seems like a fairly indirect way of supporting a company's goals. Just like if you enjoy a band's music, you don't demonstrate your support by buying second hand records...
It also worthwhile to note that the underwriters will take a cut/percentage of whatever goes to the issuing company.
When you buy Tesla stock on the stock market Tesla gets no money from you - you are actually buying the stock from another entity independent from Tesla. Tesla only receives money when the stock is sold for the first time, by the Tesla Corporation to an outsider.