I have not seen any company that is presently using bitcoin fully and then accepting bitcoin as investment except all those ICO and IEO, and the only way you can still invest your bitcoin right now and then get it multiplied is when you start trading with the coin, trading could help you continue to grow your coin, but it will require much effort from you which you also have to learned how to be able to trade.

Before we can start seeing companies that you can  see physically that is accepting bitcoin, it would be until the government fully legalize cryptocurrency or regulate it before most industries that has been interested can have the courage to come up with such idea to meet up with your own need, but for now, just to trade or pick an IEO project to invest in.