Some Rhinos grow up with rather conservative Moms, where foolishness is curtailed. Maternal raised eyebrows and pursed lips.
There is a limit somewhere on how peculiar a Rhino ought to get, but it is a limit few would exceeed, naturally.
The one demand a comic Rhino makes is an audience, and in the Wild, critters are focused on their needs and schedules, etc. So it usually makes no difference whatever how ridiculous a Rhino wants to be. Little attention gets paid.