Why would you need to do that, most good countries/airports sell tourist sims like buying a packet of chips/crispsYou're missing the point. Swapping the SIM isn't the difficult part (though it certainly is more annoying and time consuming than selecting from a list).
The hindrance is getting a new SIM in the first place. Imagine a world where you couldn't change your browser or default search engine without going to a store or waiting for the mail. Do you think that wouldn't affect competition?
This is especially true when traveling. If I go somewhere for a week, chances are I'm not going to research rates and find a place to buy a SIM. I'll just live with the outrageous roaming charges and limit my usage. But if it's just a tap away, I'll certainly do it.
Get one slide it in and it will last a week or more, it could not be easier and many airlines stock universal sims that work in many counties at set rates