Because it is funny

You can't make up this stuff. From If You Only News:

The Company Supplying Portable Toilets To Inauguration Is Called ‘Don’s Johns’ And People Are DYING

Just a few days after news broke that the Russians may or may not have secretly filmed Donald Trump enjoying a urination fetish with Russian prostitutes, inauguration organizers realized to their horror that attendees will have an abundance of giant reminders of that scandal dotted around the capital during the event.
Don’s Johns bills itself as the “the Washington area’s top provider of portable toilet rentals” but it’s name is just a smidge to close to the “Don” about to be sworn in to office. According to the Associated Press, organizers have begun frantically covering up the names on the port-a-potty units in order to avoid the embarrassment.

It’s the great port-a-potty cover-up for President-elect Donald Trump’s inauguration.

Workers preparing for the inauguration Jan. 20 have taped over the name of the company — “Don’s Johns” — that has long supplied portable restrooms for major outdoor events in the nation’s capital.
Virginia-based Don’s Johns calls itself the Washington area’s top provider of portable toilet rentals. But the name apparently strikes too close to home for inaugural organizers.
Workers have placed blue tape over the company name on dozens of portable restrooms installed near the Capitol for the inauguration.
Hilariously, the blue tape doesn’t really work. You can still see the name underneath.

For many internet users, news that Trump’s team was panicking about being compared to a literal box filled with pee was almost too much to handle.