Keep in mind that we live in a country where we are not allowed to buy and sell through bitcoin. Therefore he is selling the shirts in the fiat currency however all the shirts have Bitcoin logo over it. This is the maximum he can do to promote bitcoin. I hope when some day bitcoin may become a legal tender here also, then he can do the transactions in Bitcoin.
Link of the store is
https://store.ilmeaalim.com/en/
we can be named as bitcoin supporter and investors in which will attract criminals to make us target , we also understand that there are bad elements that is only waiting for victims ,
yes we can hide our keys in more safety places , but the chance of being force to reveal our seeds is there once they threaten our life.
actually I have A bitcoin shirt but only wearing this in a friendly meetings to lure them and try making them investors.
but I love the concept that your friend is imposing and I hope that this will be a way of making people in your community aware about bitcoin and consider investing in time.
and knowing that you are not allow in your country to purchase from bitcoin , this will be a hard task for every supporters making them aware of the market.