Really, the balanced vs. SE argument is not one for audiophiles to have. It is an argument for amplifier designers. Different design strategies will offer different tools to achieve to the end goal. A balanced design should give the designer more power output given the same voltage rails (IIRC), and it could also be a workaround for other design issues, but it could also make everything more complicated, requiring a massively complex and carefully laid out PCB.
Does any of that matter to the end user? Not really. You should be looking for "enough" power on the output to drive your transducers, or generally be looking at the final specs (noise, FR, THD, output impedance, etc.).
To the original question, there is no harm using a single ended source with a balanced amp, assuming that the amp accepts SE inputs (again, the amp will convert to balanced). Just make sure everything can connect properly (and safely!) and enjoy your music.