John Lennon himself has never been to Lithuania and has nothing to do with it, except him being a good friend to New York Fluxus Movement's Lithuanian artists Jonas Mekas and Jurgis Mačiūnas.
And still every Lithuanian knows his name and can sing at least couple of his songs. That is because the message of freedom and peace John Lennon delivered was beautiful and important to us, people of occupied and repressed country.
The fact that we now build sculptures like the ones of Frank Zappa and John Lennon is one of the true signs that the country came a long way from Soviet Union, where all the art had to represent only national heroes and idealize the regime. This little square is the evidence that the country and it's people are free.