I'm all for general politeness, and I would certainly never be rude to  somebody, I just don't like it when I am expected to act a certain way  just so somebody doesn't take offense at me, which is how I see  this issue.
As a matter of practicality, I wouldn't take a phone call at a checkout, but if somebody can do it without causing a delay, they can go right ahead as far as I am concerned. And yes I have worked as a cashier, although not when mobile phones were ubiquitous, granted.
	
		
			
		
		
	
				
			As a matter of practicality, I wouldn't take a phone call at a checkout, but if somebody can do it without causing a delay, they can go right ahead as far as I am concerned. And yes I have worked as a cashier, although not when mobile phones were ubiquitous, granted.
 
				 
 
		 
 
		
 
 
		 
 
		 
 
		 
	
 
 
 
 
		 
 
		 
 
		 
 
		 
 
		