It's just a symbolic gesture. Mosques can function perfectly well without minarets. In fact, Saudi Wahhabi mosques don't have minarets, because they're considered bid'a, innovation. But the widespread support for a minaret ban represents the frustration of the common people with the elites' indifference toward and/or complicity with Islamization and the advance of Sharia.
"75% support for the ban on minarets in London Daily News poll," from the London Daily News, December 4 (thanks to Robert):
Londoners support the Swiss government's decision to ban minarets and mosques according to a new poll in The London Daily News, further highlighting the "sensitivities" and concerns in the capital at the growing influence of Islam....
London is the home to one of the largest number of mosques in the western world,apart from Turkey, with estimates putting the number at over one hundred. The "minaret" issue has become ever more controversial with the growth of Islamic extremism in the capital, and calls by a minority for Sharia law to be observed by all.
Harrow Council recently approved the building of the largest mosque in the capital, which will see Harrow Central Mosque serving Muslim worshippers from across north London when it is built on Station Road. Construction News in a report said:
"The designs include a 40m-high minaret, a gym, a crèche and a café within the 5,745 square metre developments. It is expected to open next year after Harrow Council approved changes to the original plans, which were passed in June 2000."
Increasingly London Muslims are demanding mosques to be built with traditional minarets, which reflect the liberal regime in place in the capital city. There are an estimated 1 million Muslims in London.