Skipped over the entire thread to post:
Around here, those are called “portalets” by everyone. Stress on the “-lets”. A jokey/kiddie name for them is “porta-potties”. Use of any other name for these items is not likely to be understood by many locals.
Several places online (including here) I’ve found the following list of portable toilet brand names:
One I’ve seen personally, and chuckled at: Midwest Pottyhouse
I haven’t heard that term since I was in boy scouts, over 50 years ago, at which time it referred to any temporary latrine, usually while camping so there was no structure, just a hole in the ground and a place to sit.
Years ago there was a port john company whose logo included the words “Heeeerrrre’s Johnny!” Mr. Carson got wind of it, sued them, and they had to drop the line. SOME people are SO sensitive. 
I’ve called it port-o-john, but I’ve also called it a plastic outhouse.
Port-A-Potty or Port-O-John
port-o-potty
Portalet
Earl Braxton, to be specific. He tried again in 2006 to register the name, after Carson’s death, but the Trademark Trial and Appeal Board ruled that the rights of publicity to “Here’s Johnny” had passed on to Carson’s estate and that Braxton was still bound by the original injunction.
I did. Thanks to a bunch of you.
JR thought that they were porta-pottys & I was the only one who called them porta-johns. It’s not that I wouldn’t know what you were talking about if you called it a porta-potty but I tend to not use the latter word if I’m not talking to a toddler. Porta-john is also not as alliterative & therefore easier to say. (Try saying them both fast & see which one becomes a tongue twister.)
Yay! What’d we win?
Were you informed what the acronym stands for?
WTF? Way more people are calling them port-a-potties than port-a-johns here?
Around here we called them Poo Boys.
So, no one has heard “Sani-kan”? Perhaps that is a brand name.
I was wondering about that myself. I’m guessing it’s the technicality that his friend said that nobody calls them “Porta Johns,” otherwise, it doesn’t make sense.
The privilege of saying, “I told you so. Tbhthbhtbhtttbhtbhhtbtttt” [del]:p[/del]
I know several people here (Oregon) that call them Honey Buckets. When I first moved here it took me a while to figure out what the hell they were talking about.
Port-a-Potty