Avoiding expected rhymes was often done in German songs, not so much to avoid profanity, but to avoid a word disrespectful to the respective reigning nobility in a part of Germany. These were quite artful songs, formerely omitting the rhyme word would not have helped against punishment. The idea was to lead the listener to expect a disrespectful rhyme word but to end the verse with a slight change of tune and rhyming pattern so that everything rhymed perfectly but not as expected.

These were songs that did rhyme but not at that place and with that word everybody expected.

Wolfgang