If you tell people that you bought stuff in the internet or even in a shop with Bitcoin, people will become aware of Bitcoin, more so if the stuff that you are showing them have value when you bought it with fiat money, what do you think about this?
It's a good way to spread bitcoin to those people that didn't know yet the use and existence of bitcoin. By showing them the stuff that you have bought and telling them that you just bought it using bitcoin, I am pretty sure that they will be curious about it.
And their curiosity will be our ace to make the people become aware about bitcoin and a good way to spread the usage of bitcoin around the globe. It's a small marketing technique but I am sure that it will surely help bitcoin to raise it's demand and price.