Just a feeble try, er, attempt, at humour, Gnu. A play on the meanings of 'sentence.' I do agree with you, and I'll bet I have even more grammatical bees in my bonnet than you have. I won't sing ungrammatical songs. They make me wince.
People who write such songs DON'T CARE, though.
I'm not a grammarian. Just someone who likes English, as you do yourself.