Yes, it did happen. Several times. In 1974. Jeremy Thorpe did a tour of seaside resorts to drum up support from voters in the run-up to the second general election of the year, which was held in October that year.
I witnessed one of these events at Bude, Cornwall. It was absolutely bizarre. Jeremy Thorpe's hovercraft arrived from the sea and landed on busy Summerleaze beach, on which hordes of tourists were sunbathing in their swimming trunks/bikinis. Thorpe then came out of the hovercraft and addressed the populace from the running board of his craft. He stood there in a three-piece suit and trilby hat, in the blazing sunshine. I remember that Angela Rippon, the broadcaster, was standing beside him with a film crew for Westward Television.
You couldn't make it up.
In order to prove that I am not dreaming, here below is a photo of said tour from the BBC archive (which I have reproduced in low resolution format for indicative purposes only on this non-profit-making site.) The photo seems to have been taken on a rather more inclement day than the one when I witnessed Thorpe's coming.
There is a BBC archive article on the October 1974 general election.
Footnote: Interestingly, Paul Tyler was actually an MP at the time of this tour - he was MP for Bodmin from the first 1974 general election in February until the second one in October, so that when he came back to the Commons in the 1990s to represent North Cornwall, he was treated well ahead of the queue of new MPs for coat/sword pegs etc (because the divvying-up is all done on the date of your first entrance to the Commons).